Confounded Rules! Spotlight: Surprise Rules in Advanced Dungeons & Dragons
- Dungeoneers Guild Games
- 2 days ago
- 24 min read
Updated: 2 hours ago
This article analyzes and clarifies the rules concerning combat surprise in First Edition Advanced Dungeons & Dragons.
By R. Nelson Bailey
As with many rules in First Edition Advanced Dungeons & Dragons (AD&D), the mechanics governing surprise—where one side in an encounter is caught unguarded by the other—are particularly fraught with confusion and misunderstanding. The rules are scattered across several sections of different books. The wording is often opaque and convoluted, and the examples provided are sometimes unclear or incomplete.
This article aims to show, step by step and through numerous examples, how surprise is intended to function in the First Edition game. By examining the cumbersomely worded text in the Dungeon Masters Guide (DMG), it attempts to clarify how these rules are meant to operate within the framework of the game. This should be understood as an examination of the rules themselves rather than an evaluation of their merits—whether they are good or bad, useful or lacking.
While every edition of the game has its own method for determining surprise, this article does not attempt to declare one approach superior (should such a judgment even be possible). Rather, its goal is to explain how the First Edition rules are intended to operate. Whether you, as the Dungeon Master (DM), choose to use these rules in whole, in part, or not at all is entirely your prerogative. This article does not suggest that the surprise rules must be followed exactly as written.
The first thing the uninitiated will notice about surprise in First Edition is that it likely contains the most complex surprise system of any edition. Surprise is divided into segments, during which the unsurprised side may act before normal combat begins. Compare this with Second Edition, where the unsurprised side gains a single free attack.
The second thing the uninitiated will notice—and this often surprises players familiar with later editions—is how deadly surprise can be for the losing side. To illustrate this, consider the following explanation from Polyhedron magazine’s “Dispel Confusion” feature:
Q: I was visiting a friend and got into one of his AD&D games. We met a group of three gargoyles at an intersection, but we weren't allowed to swing at them until they took over 40 swings at us! The DM said we were surprised. I've never been that surprised. Is this a variant?
A: No, but it sounds like you were badly surprised. If you check the DMG (pg. 62, column 1), you'll find that each surprise segment is treated as a whole round for attacks, and 12 attacks per segment is the rule in this case (3 gargoyles times 4 attacks each). If you rolled a 1 and the DM rolled a 6, they would have had 5 surprise segments and could have gotten in a total of 60 attacks — assuming that they didn't have to spend any segments moving in. Players, don't despair; you can take measures to prevent surprise, such as describing who's looking where and when, having a ranger or monk along, and so forth. The DM should adjust surprise rolls according to terrain and specific actions, so you can avoid being surprised most of the time. But it can get nasty with bad rolls, and you can't be super-alert all the time. [1]
As this demonstrates, surprise can be extremely deadly. Let us therefore examine the First Edition AD&D surprise rules more closely to determine exactly what they do—and do not—say.
[1] “Dispel Confusion” (Polyhedron, Issue 1, 1981), p. 3.
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What is Surprise?
In First Edition Advanced Dungeons & Dragons, surprise occurs when one or both parties in an encounter are caught unaware by the other. Each side rolls to determine whether it is surprised by the opposing side. Many factors—light, location, noise, and special senses—may modify the roll.
If the dice indicate that one side is surprised, the opposing side may act for a number of surprise segments. During these segments, the acting side may move, attack, cast spells, or attempt parley. Once the surprise period ends, all actions (such as melee combat) proceed as normal.
The Surprise Sequence
The determination and resolution of surprise occur in three steps:
1. Roll for surprise
2. Determine encounter distance
3. Take actions
If the dice indicate that no surprise occurs, the sequence ends after Step 1, and play proceeds normally.
The sections below describe each of these steps clearly and concisely for both DMs and players.
STEP 1. THE SURPRISE ROLL
Both sides—the Party and their Opponent—roll a die to determine surprise. [2] In most cases, this roll is made with a d6, although certain character classes or monsters may use a different die, such as a d8 or d10. (The Monster Surprise Chance Table at the end of this article lists all of the First Edition monsters that possess special surprise abilities and their ranges.)
Under normal circumstances, surprise occurs on a roll of 1 or 2, or their “surprise range.” [3] Each side rolls separately: the Party rolls to determine whether they are surprised, while the Opponent rolls to determine whether it is.
If a monster has a different chance to surprise—for example, 1-in-10—the Party rolls a d10 to determine whether they are surprised.
When determining surprise for a group, the individual with the least chance of being surprised determines the chance for the entire group. Thus, if a group includes a ranger, the normal chance of being surprised is 1-in-6 rather than 2-in-6. [4] The converse does not apply: a member’s improved chance to surprise others does not benefit the group; instead, the group uses the worst such chance among its members. [5]
[2] Dungeon Masters Guide, p. 61. “Surprise is determined by rolling a six-sided die for each party concerned.”
[3] Dungeon Masters Guide, p. 61. “Surprise is usually expressed as a 2 in 6 chance for all parties concerned.”
[4] Dungeon Masters Guide, p. 61. “Using the most favorable member of the party concerned, i.e., a ranger, surprised only on a roll of 1, will represent the whole of a group of other character types.”
[5] As shown with the ranger, elf, and halfling descriptions in the Players Handbook.
Modifiers to the Surprise Roll
Many factors may negate or increase the chance of surprise for one or both parties, depending on the circumstances of the encounter. [6] The presence of light, failure on an open doors roll, or being distracted are a few examples. Surprise chances may also be modified by situational factors—including lighting, noise, and terrain. [7] The First Edition game does not provide the DM with a list of modifiers to adjust a surprise roll. Instead, it is left up to the discretion of the Dungeon Master to determine these on a case-by-case basis. [8] (The Surprise Modifiers Table section below provides a detailed listing of modifiers.)
[6] Dungeon Masters Guide, p. 62.
[7] Dungeon Masters Guide, p. 63. See the “Distance” heading.
[8] Dungeon Masters Guide, p. 62. As noted in the “Factors Contributing to Surprise” Section: “While each possible cause of surprise could be detailed, with a matrix and factors of time for recovery from the condition calculated to a nicety, the overall result would not materially add to the game — in fact, the undue complication would detract from the smooth flow of play.”
Situations with No Chance of Surprise
In some circumstances, the DM may rule that one or both sides need not roll for surprise because no chance of surprise exists. [9]
Example: A monster occupies an area with a very narrow entrance connected to a 30-foot passage in a dungeon. The creature has been alerted to the Party’s approach, as they carry a bright continual light in an otherwise dark area. In this case, the DM may rule that the Party must roll for surprise, while the monster does not, as it is already aware of their approach.
[9] Dungeon Masters Guide, p. 62. “In any event, it is of utmost importance to realize that surprise can be and often is unilateral. That is, one party can be surprised while the other, somehow aware of the other's presence, can NOT be so taken. In all such cases, merely roll for the party which is subject to the condition and do not roll for the other.”
Surprise Roll Results
The roll of each die determines whether surprise occurs. Possible surprise results of the dice rolls are mutual surprise, one side surprised, or no surprise: [10]
A) Mutual Surprise occurs when both sides’ die rolls indicate surprise. This situation has two possible outcomes:
1. Both sides roll the same number. For example, both sides roll a 1 when surprise occurs on a 1–2 on a d6. In this case, the mutual rolls negate all surprise, and neither side may act.
2. Both sides are surprised, but one side rolls higher. In this case, the number of surprise segments is reduced. Subtract the lower roll from the higher roll; the result is the number of segments during which the side with the higher roll may act. The side with the higher roll acts during the remaining surprise segments. [11]
Example: Both sides are surprised on a roll of 1–2 on a d6. The Party rolls a 1, and their Opponent rolls a 2, indicating that both sides are surprised. Because the Opponent rolled the higher number, they may act for 1 segment against the party (2 − 1 = 1).
B) One side is surprised. The surprised side is inactive, while the opposing side may act. The duration of surprise is normally equal to the surprised side’s die roll. In some cases, as shown in the DMG examples, this duration may be reduced by the opposing roll.
C) No side is surprised. When neither side is surprised, continue through the Combat Sequence (DMG, p. 61) steps as normal.
[10] Dungeon Masters Guide, p. 62. See the surprise chart.
[11] Dungeon Masters Guide, p. 71. The “Example of Melee” section illustrates the concept that the difference between both surprise die rolls determines the number of segments the surprise side is inactive: “[the DM] rolls a d6 for party B and a 2 comes up. The leader for the players rolls and gets a 4 for party A. Party B is surprised (since they rolled a 2), and will be inactive for 2 segments.”
“Lost” Surprise Segments
The surprise die roll serves two purposes. First, it determines which side is surprised; second, it determines how long that surprise lasts. Each surprise segment represents six seconds of time, and a surprise round may consist of one or more such segments. [12] When a side is surprised, its base duration of surprise is equal to its own die roll. Thus, a roll of 1 indicates 1 segment of inactivity, a roll of 2 indicates 2 segments, and so on.
When a side has a reduced chance of being surprised (e.g., a 1-in-6 chance from having a ranger in the party), that amount is subtracted from the opponent’s chance to surprise them. Since the normal surprise range is 1–2, this typically results in a reduction of 1, as the lowest possible chance on a d6 is 1-in-6.
a) When both sides are surprised, the duration of surprise is reduced. Subtract the lower die roll from the higher; the result indicates the number of segments during which the side with the higher roll may act. [13]
b) When only one side is surprised, the duration is based on the difference between the two rolls; when the opposing roll does not reduce it, this is equal to the surprised side’s own die roll. However, if both sides’ rolls fall within their respective surprise ranges, the result is treated as mutual surprise, and the duration is reduced by subtracting the lower roll from the higher.
The table below shows the number of “lost” segments in the surprise round when both parties are surprised. [14]
Surprise Dice Difference | Lost Segments | ||
0 | 0 | ||
1 (2-1, 3-2, etc.) | 1 | ||
2 (3-1,4-2, etc.) | 2 | ||
3 (4-1,5-2, etc.) | 3 |
[12] Dungeon Masters Guide, p. 61. “Each 1 of surprise equals 1 segment (six seconds) of time lost to the surprised party.”
[13] Dungeon Masters Guide, p. 62. See the “Distance, Example” subsections.
[14] Dungeon Masters Guide, p. 61. Table from that page reproduced here.
Non-Standard Surprise Rolls
The standard surprise die for most player characters and monsters is the d6. However, some monsters use other dice types or have their chance of surprise expressed as a percentage. For example, drow surprise others 75% of the time (1–15 on a d20), while they themselves are surprised only 12.5% of the time (1 on a d8).
This creates a problem when each side rolls a different die with different probability ranges. It also complicates determining the number of surprise segments. For example, if the Party rolls a d20 to determine whether a drow surprises them, how many segments of surprise occur if a 14 is rolled and the drow roll a 7 on a d8? Interpreted literally, this could suggest more than 7 segments, even though a surprise round contains no more than 6 segments.
The simplest solution is to convert each die roll to its percentage equivalent (Table 1 below) and then translate that result into the corresponding number of surprise segments using Table 2 (see below).
This table shows the percentage of each roll for different die types.
Table 1. Die Type to Percent
Chance | d6 | d8 | d10 | d12 | d20 |
1 | 16.67% | 12.50% | 10.00% | 8.33% | 5.00% |
2 | 33.33% | 25.00% | 20.00% | 16.67% | 10.00% |
3 | 50.00% | 37.50% | 30.00% | 25.00% | 15.00% |
4 | 66.67% | 50.00% | 40.00% | 33.33% | 20.00% |
5 | 83.33% | 62.50% | 50.00% | 41.67% | 25.00% |
6 | 100.00% | 75.00% | 60.00% | 50.00% | 30.00% |
7 | -- | 87.50% | 70.00% | 58.33% | 35.00% |
8 | -- | 100.00% | 80.00% | 66.67% | 40.00% |
9 | -- | -- | 90.00% | 75.00% | 45.00% |
10 | -- | -- | 100.00% | 83.33% | 50.00% |
11 | -- | -- | -- | 91.67% | 55.00% |
12 | -- | -- | -- | 100.00% | 60.00% |
13 | -- | -- | -- | -- | 65.00% |
14 | -- | -- | -- | -- | 70.00% |
15 | -- | -- | -- | -- | 75.00% |
16 | -- | -- | -- | -- | 80.00% |
17 | -- | -- | -- | -- | 85.00% |
18 | -- | -- | -- | -- | 90.00% |
19 | -- | -- | -- | -- | 95.00% |
20 | -- | -- | -- | -- | 100.00% |
The following table shows how the six segments of a surprise round correspond to cumulative percentages.
Table 2. Surprise Segments to Percent
Segment | Percent | ||
1 | 0–16.67% | ||
2 | 16.68–33.33% | ||
3 | 33.34–50.00% | ||
4 | 50.01–66.67% | ||
5 | 66.68–83.33% | ||
6 | 83.34–100% |
Example: The Party contains a ranger, who is surprised only on 1 on a d6 (16.67%). They encounter some Drow, who surprise others 75% of the time (1–15 on a d20) and are themselves surprised only 12.5% of the time (1 on a d8). The ranger reduces the chance that the Drow will surprise the Party by 16.67%, lowering it from 75% to 58.33%. The Party therefore has a 58.33% chance of being surprised, while the Drow have only a 12.5% chance. Both sides now determine their surprise result. If percentile dice are used, suppose:
The Party rolls 23%, and the Drow roll 71%.
The Party’s roll falls within its surprise range, while the Drow’s does not. Comparing the Party’s result to Table 2, 23% corresponds to 2 segments.
Thus, the Drow surprise the Party for 2 segments.
Examples of Surprise Die Rolls
To give the reader a clearer idea of what specific surprise die rolls mean in terms of who is and is not surprised, the following examples illustrate these outcomes in action.
Example 1
Both the Party and the Opponent are surprised on a roll of 1–2 on a d6. The possible results are as follows:
Party rolls 1, and the Opponent rolls 2.
Both die rolls fall within their respective surprise ranges, indicating mutual surprise. Subtracting the lower roll from the higher gives 1 (2 − 1 = 1). Because the Opponent rolled the higher number, the Party is inactive for 1 segment.
Party rolls 2, and the Opponent rolls 1.
Both die rolls again fall within their surprise ranges, indicating mutual surprise. Subtracting the lower roll from the higher gives 1 (2 − 1 = 1). Because the Party rolled the higher number, the Opponent is inactive for 1 segment.
Both sides roll 2.
Both die rolls fall within the surprise range. Because the rolls are equal, the result is mutual surprise, and neither side may act.
Both sides roll 3 or greater.
Neither die roll falls within the surprise range. No surprise occurs.
The Party rolls 4, and the Opponent rolls 1.
The Opponent’s die falls within their surprise range, while the Party’s does not. Therefore, only the Opponent is surprised. Because only the Opponent is surprised, they are inactive for a number of segments equal to their roll: 1 segment.
Example 2
The Party is surprised on a roll of 1–2 on a d6, while the Opponent is surprised only on a roll of 1.
Party rolls 1, and the Opponent rolls 2.
The Party’s die is within their surprise range, while the Opponent’s is not. Because only the Party is surprised, they are inactive for a number of segments equal to their roll: 1 segment.
Party rolls 2, and the Opponent rolls 1.
Both rolls fall within their respective surprise ranges, indicating mutual surprise. Subtracting the lower roll from the higher gives 1 (2 − 1 = 1). Because the Party rolled the higher number, they are inactive for 1 segment.
Both sides roll 2.
The Party’s die is within their surprise range, while the Opponent’s is not. Because only the Party is surprised, they are inactive for 1 segment (2 reduced by the Party’s 1-step advantage in avoiding surprise).
Example 3
This example shows a matrix of all possible results when the Party has a 1–4 chance to surprise others, and the Opponent has a 1–2 chance.
Party’s Roll: The roll made to determine whether the Party is surprised, using the Opponent’s chance to surprise. In this case, the surprise range is 1–2 on a d6.
Opponent’s Roll: The same as above, except the DM makes the roll using the Party’s chance to surprise (i.e., 1–4 on a d6).
Red = surprise range. Seg. = surprise segment.
|
| Opponent’s Roll |
|
| ||
Party’s Roll | 1 | 2 | 3 | 4 | 5 | 6 |
1 | Mutual Surprise No Actions | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Opponent Surprised 3 segs. | Party Surprised 1 seg. | Party Surprised 1 seg. |
2 | Party Surprised 1 seg. | Mutual Surprise No Actions | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Party Surprised 2 segs. | Party Surprised 2 segs. |
3 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Opponent Surprised 3 segs. | Opponent Surprised 4 segs. | No Surprise | No Surprise |
4 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Opponent Surprised 3 segs. | Opponent Surprised 4 segs. | No Surprise | No Surprise |
5 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Opponent Surprised 3 segs. | Opponent Surprised 4 segs. | No Surprise | No Surprise |
6 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | Opponent Surprised 3 segs. | Opponent Surprised 4 segs. | No Surprise | No Surprise |
Example 4
This example shows a matrix of all possible results when the Party has a 1-in-6 chance to be surprised, and the Opponent surprises 5-in-6 times.
Party’s Roll: The roll used to determine whether the Party is surprised, based on the Opponent's chance to surprise. In this case, the base range is 1–5 on a d6. Because the Party is only surprised on a roll of 1 (one step better than the standard 1–2 range), this reduces the Opponent's chance to surprise by 1, yielding a final range of 1–4 on a d6.
Opponent’s Roll: The same as above, except the DM makes the roll using the Party’s chance to surprise (i.e., 1–2 on a d6).
Red = surprise range. Seg. = surprise segment.
|
| Opponent’s Roll |
|
| ||
Party’s Roll | 1 | 2 | 3 | 4 | 5 | 6 |
1 | Mutual Surprise No Actions | Opponent Surprised 1 seg. | Party Surprised 1 seg. | Party Surprised 1 seg. | Party Surprised 1 seg. | Party Surprised 1 seg. |
2 | Party Surprised 1 seg. | Mutual Surprise No Actions | Party Surprised 2 segs. | Party Surprised 2 segs. | Party Surprised 2 segs. | Party Surprised 2 segs. |
3 | Party Surprised 2 segs. | Party Surprised 1 seg. | Party Surprised 3 segs. | Party Surprised 3 segs. | Party Surprised 3 segs. | Party Surprised 3 segs. |
4 | Party Surprised 3 segs. | Party Surprised 2 segs. | Party Surprised 4 segs. | Party Surprised 4 segs. | Party Surprised 4 segs. | Party Surprised 4 segs. |
5 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | No Surprise | No Surprise | No Surprise | No Surprise |
6 | Opponent Surprised 1 seg. | Opponent Surprised 2 segs. | No Surprise | No Surprise | No Surprise | No Surprise |
Reaction Adjustment Modifier
An individual’s Dexterity Reaction Adjustment modifies the number of segments for which that individual is surprised. [15] A positive Reaction Adjustment reduces the number of surprise segments by the value of the adjustment; a negative Reaction Adjustment increases the number of surprise segments by that value. For example, if a party is surprised for 2 segments, a character with a 16 Dexterity (+1 Reaction Adjustment) is surprised for only 1 segment. In comparison, a character with a 5 Dexterity (–1 Reaction Adjustment) is surprised for 3 segments. Opponents may not attack, fire missiles at, or otherwise target individuals who are not surprised and can react. [16] Such individuals, however, may not take actions against their opponents until surprise is over and initiative is rolled.
[15] Dungeon Masters Guide, p. 62. See the “Surprise, Dexterity Reaction in Surprise” subsection.
[16] Dungeon Masters Guide, p. 71. As shown in the “Example of Melee” section: “Aggro would normally get another chance to hit Balto, who would be inactive for another segment, but Balto's dexterity allows him a +1 reaction adjustment, which means that he personally will be surprised for one less segment than the rest of his party. So this segment he is up and on his guard, and Aggro does not get another hit attempt this round.”
STEP 2. DETERMINE SURPRISE DISTANCE
Once surprise is determined, the encounter distance is established. The method for determining distance depends on whether the encounter occurs indoors or outdoors.
1) Indoors: For surprise to occur, encounter distance must be between 1” and 3”. [17]
2) Outdoors: In an outdoor setting, encounter distance is 60 to 240 yards (6d4 × 10). If either side is surprised, subtract 1 from the 6d4 roll for each segment of surprise. [18] For example, if the surprise roll is 1 on a d6, the encounter distance becomes (6d4 − 1) × 10 yards. If the roll is 2, it becomes (6d4 − 2) × 10 yards; if 3, (6d4 − 3) × 10 yards, and so on.
[17] Dungeon Masters Guide, p. 62. See the “Distance, Surprise” subsection.
[18] Dungeon Masters Guide, p. 49. See the “Encounter Distance” section for a more detailed accounting of this process.
STEP 3. ACTIONS DURING SURPRISE
The surprised side may take no actions during inactive segments, but suffers no penalties to Armor Class, Dexterity, or saving throws. [19]
Each surprise segment allows the active side to take actions against the inactive side as if it were a full melee round. [20] Combatants achieving surprise may opt to take any of the following actions during each segment:
a) Avoid the encounter
b) Move
c) Make a melee attack
d) Fire a missile weapon
e) Cast a spell
f) Use a special ability
g) Use a magic item
h) Turn undead
a) Avoid Encounter: The surprising party can opt to flee, parley, or await the actions of the other party.
b) Movement During Surprise: A character may move a distance in feet equal to their Movement Rate during each segment of surprise. Thus, a character with a 12″ Movement Rate may move 12 feet per segment. [21] Melee combat occurs only within Striking Range—approximately 10 feet or less. [22] If the target is farther away, the attacker must expend movement to reach the opponent before making a melee attack.
Example: At the start of a surprise period lasting 3 segments, a fighter with a movement rate of 6″ finds himself 20 feet from the nearest enemy. He advances toward his opponent, covering 6 feet during the first segment and 6 more feet during the second. At the beginning of the third segment, he is 8 feet away, placing him within striking distance. He then makes a melee attack during the third segment.
c) Melee Attacks: Any attacker within 10’ (i.e., Striking Range) may attack with melee weapons. Combatants outside this range must first move to the target. [23] During each surprise segment, a character or monster may attack as if it were a full melee round. This includes their full number of attacks, such as monsters with multiple attack routines. Fighters and monsters making multiple attacks with the same weapon also attack at their normal rate during each segment. [24]
Example 1: A fighter with two attacks per round may attack twice in each segment.
Example 2: A hydra with 10 heads attacks with each head every segment, as it normally has 10 attacks per melee round. If it surprises its opponents for 3 segments, it may therefore make a total of 30 attacks.
d) Missile Fire: Missile weapons discharge at their normal rate of fire during each segment. Thus, a bow may fire twice per segment, and up to three darts may be thrown in a segment. However, if the surprising party has the weapon and ammunition already in hand and ready to fire at the start of surprise, they may fire at three times the normal rate. [25]
Example: A thief with a short bow is expecting a troop of goblins to approach his position shortly. When they arrive, he wins surprise by 3 segments. With bow in hand and arrows readily accessible, he fires six arrows per surprise segment, for a total of 18 shots over the full 3 segments.
e) Spellcasting: Spellcasters may cast spells during surprise. Each segment of surprise equals one segment of casting time. Therefore, only spells with short casting times can be completed during the surprise period. If the casting time is longer than the available surprise segments, the spell continues into the next round and completes when its casting time is fulfilled. [26] Regardless of the spell’s casting time or the number of surprise segments available, a spellcaster may cast only one spell during surprise. [27]
Example 1: A magic-user has two surprise segments in which to act. He casts sleep (casting time: 1 segment). The spell takes effect during the first segment. However, the magic-user may not cast another sleep spell during the second segment (though he could probably take another action).
Example 2: The same magic-user instead casts fireball. Two of the spell’s three casting segments occur during the surprise period. The final segment of casting occurs after the surprise period ends, and the spell then takes effect.
f) Special Abilities: These include spell-like abilities or special abilities possessed by a monster or character. Like spells, such abilities may be used during surprise and are subject to segment-based timing. Monster spell-like abilities have a casting time of 1 segment. [28]
g) Magic Items: Treat as a spell if the item has a casting time.
[19] Dungeon Masters Guide, p. 62.
[20] Dungeon Masters Guide, p. 62. “Because the party surprised is (relatively) inactive, the surprising party will be able to attempt telling blows during each segment of surprise as if the segment were an entire round!”
[21] Advanced Dungeons & Dragons Players Handbook (TSR, 1978), p. 102. See the “Movement in Dungeons” section.
[22] Dungeon Masters Guide, p. 66. See the “Close to Striking Range” section.
[23] Dungeon Masters Guide, p. 66. See the “Close to Striking Range” section.
[24] Dungeon Masters Guide, p. 62. See the “Surprise, Example 2” subsection. “A fighter able to attack twice during a normal round of combat will be able to do so twice during each surprise segment.”
[25] Dungeon Masters Guide, p. 62. See the “Surprise, Example 2” subsection.
[26] Dungeon Masters Guide, p. 61. As noted in the “Surprise” section: “Most spells cannot be cast in a single segment, although first level magic-user/illusionist spells are usually but 1 segment long, as are some other spells, and these spells are possible to use in a surprise segment. Other, longer casting time spells can only be begun in the first segment of surprise.”
[27] Dungeon Masters Guide, p. 71. As noted in the “Example of Melee” section: “Party A has a chance to hit in each segment as if they were full rounds (this does not apply to spell use, of course).”
[28] “Dispel Confusion” (Polyhedron, Issue 9, 1982), p. 6. The exact answer found here is: “Spell-like powers are not spells, and do not need to be "cast." They can be produced in total silence, for example, and in 1 segment of concentration. Thus, they can only be interrupted if a blow connects during that same segment and if the creature sees a swing coming, it can easily delay a bit to avoid interruption.”
SURPRISE MODIFIERS
First Edition AD&D provides no fixed set of surprise modifiers. Instead, the DM is expected to apply them as circumstances dictate. Table 3. Surprise Modifier Table below offers a list of common modifiers that may be used when determining surprise. This list is not exhaustive, however, since each situation is unique with respect to environment, magic, and the creatures involved.
The modifiers in the table are cumulative, and several may apply in a given situation. Thus, a thief wearing boots of elvenkind (–1 to the opponent’s surprise roll) and also invisible (–1) imposes a total penalty of –2 to the opponent’s surprise check.
In most situations, the chance to be surprised should rarely fall below 1 on a d6 (16.67%), which would make one unsurprisable. Conversely, it should never exceed 5-in-6 (83.33%), which would be an automatic surprise. As a general rule, there should always remain some chance that the surprise is detected before the attack is sprung—whether by luck or by a sixth sense that warns the intended victim at the last moment.
Table 3. Surprise Modifier Table
Condition | Chance to Surprise | Chance to be Surprised |
Alerted or guarding | +1 (or +16.67%) | –1 (or –16.67%) |
Concealed – fully (90%+) | –3 (or –50%) | -- |
Concealed – mostly (50%+) | –2 (or –33.33%) | -- |
Concealed – partly (25%+) | –1 (or –16.67%) | -- |
Deafened | –1 (or –16.67%) | +1 (or +16.67%) |
Distracted | –1 (or –16.67%) | +1 (or +16.67%) |
Employing ESP or similar thought-reading magics | +2 (or +33.33%) | –2 (or –33.33%) |
Invisible – moving* | –1 (or –16.67%) | –1 (or –16.67%) |
Invisible – not moving* | –1 (or –33.33%) | –2 (or –33.33%) |
Large group (10+) | –1 (or –16.67%) | –1 (or –16.67%) |
Noise – loud (e.g., melee, talking loudly, or moving in metal armor) | –1 (or –16.67%) | +1 (or +16.67%) |
Noise – extreme (e.g., mass melee, lightning bolt, or horn sounding) | –2 (or –33.33%) | +2 (or +33.33%) |
Noisy environment (e.g., crowded inn or strong wind) | +1 (or +16.67%) | –1 (or –16.67%) |
Opening a door | –2 (or –33.33%) | +2 (or +33.33%) |
Silent | –1 (or –16.67%) | –1 (or –16.67%) |
Terrain – Smooth (e.g., dungeon floor clear of debris) | -- | -- |
Terrain – Cluttered (e.g., rock-strewn floor) | –1 (or –16.67%) | +1 (or +16.67%) |
Terrain – Dense (e.g., leaf-covered forest) | –2 (or –33.33%) | +2 (or +33.33%) |
Unable to see (e.g., blinded or in darkness) | –1 (or –16.67%) | –1 (or –16.67%) |
Unexpected appearance** | –3 (or –50%) | –3 (or –50%) |
Using a light source in an otherwise dark area | –2 (or –33.33%) | +2 (or +33.33%) |
Chance to Surprise: Modifies the opponent’s roll to determine whether they are surprised. Subtract negative modifiers from the opponent’s roll (making surprise more likely); add positive modifiers (making surprise less likely).
Chance to Be Surprised: Modifies your own roll to determine whether you are surprised. Add positive modifiers to your roll (making you easier to surprise); subtract negative modifiers (making you harder to surprise).
-- = no modifier.
* Assuming the opponent has no means to detect invisibility.
** Such as appearing instantly via teleport, emerging from a wall while ethereal, or similar magical effect.
Table 4. Monster Surprise Chance Table
Monster | Chance to Surprise* | Chance to be Surprised** |
Aerial Servant | 1–4 | -- |
Ape, Carnivorous | -- | 1 |
Atomie | 90% (1–9 on a d10) | 10% (1 on a d10) |
Aurumvorax | 1–3a | -- |
Barghest | 1–3 | -- |
Barkburr | always unless recognized | -- |
Basilisk, Greater | -- | 1 |
Bookworm | 95% (1–19 on a d20) | as a ranger |
Brownie | -- | never |
Buckawn | -- | never |
Bugbear | 1–3 | -- |
Bullywug | 1–3b or 1–5 when hopping | -- |
Caterwaul | -- | 10% (1 on a d10) |
Cave Moray | 1–5 | -- |
Cheetah | 1–3 | 1 |
Cloaker | -- | never from the rear |
Crab, Giant | 1–4 | -- |
Crayfish, Giant | 1–3 | -- |
Crimson Death | 1–5 | -- |
Crocodile (all) | 1–3 | -- |
Daemon, Pisco- | -- | never |
Demodand, Shator (Shaggy) | -- | 10% (1 on a d10) |
Deva, Astral | -- | never |
Devil, Barbed | -- | never |
Dinosaur, Compsognathus | 1–3 | -- |
Doppelganger | 1–4 | -- |
Dragon Horse | -- | never |
Dwarf, Duergar | 1–3 | 10% (1 on a d10) |
Eagle | -- | never |
Eagle, Giant | -- | neverc |
Elf | 1–4b | -- |
Elf (player character) | 1–4d | -- |
Elf, Drow | 75% (1–15 on a d20) | 12.5% (1 on a d8) |
Elfin Cat | 1–5 | 5% (1 on a d20) |
Ettin | -- | 1 |
Executioner's Hood | 1–3 | -- |
Fire Snake | 60% (1–6 on a d10) | -- |
Frog, Giant | 1–3b | -- |
Gelatinous Cube | 1–4 | -- |
Giant, Cloud | -- | 1 |
Giant, Fog | 80% (1–8 on a d10)e | 1 |
Giant, Formorian | +1–+3f | never |
Gloomwing | 1–3 | -- |
Gnome, Deep | 90% (1–9 on a d10) | 8.33% (1 on a d12) |
Gorilla Bear | -- | 15% (1–3 on a d20) |
Green Hag | 1–5 | 5% (1 on a d20) |
Grig | 90% (1–9 on a d10) | 5% (1 on a d20) |
Grim | -- | 10% (1 on a d10); never by Evil creatures |
Grippli | 1–4 | -- |
Grue, Chaggrin | 1–5a | -- |
Grue, Ildriss | 1–4 | -- |
Halfling | 1–4b | -- |
Halfling (player character) | 1–4d | -- |
Hell Hound | 1–4 | 1 |
Hook Horror | -- | 10% (1 on a d10) |
Invisible Stalker | 1–5 | -- |
Jaguar | -- | 1 |
Jermlaine | 1–5 | -- |
Kampfult | 1–3 | -- |
Kech | 1–5 | -- |
Khargra | 87.5% (1–7 on a d8) | -- |
Kuo-toa | -- | 1 |
Kuo-toa, Monitor | -- | 10% (1 on a d10) |
Leopard | -- | 1 |
Leprechaun | -- | never |
Lion (all) | -- | 1 |
Lizard, Minotaur | 1–4 | -- |
Luck Eater | 1–4 | -- |
Lurker Above | 1–4 | -- |
Lycanthrope, Wererat | 1–3 | -- |
Lycanthrope, Werewolf | 1–4 | -- |
Lynx, Giant | 1–5 | -- |
Margoyle | 80% (1–8 on a d10) | -- |
Meenlock | 80% (1–8 on a d10) | -- |
Men, Nomad | 1–4b | -- |
Minotaur | -- | 1 |
Mobat | 1–3g | -- |
Modron (hierarchs) | -- | never |
Modron, Quadrone | -- | never |
Monk | -- | 1–2 or lower |
Moon Dog | 1–3 | never |
Necrophidius | 1–3 | -- |
Needleman | 75% (1–15 on a d20) | -- |
Neo-otyugh | -- | never |
Ogre, Aquatic | 1–4 | -- |
Opinicus | 1–5 or 1–3 | never |
Otyugh | -- | never |
Owl (all) | 1–5g | -- |
Phoenix | -- | never |
Piercer | 95% (1–19 on a d20) | -- |
Pike, Giant | 1–4 | -- |
Planetar | -- | never |
Quickling | -- | never |
Quickwood | -- | never |
Ranger | 1–3 | 1 |
Raven (all) | -- | never |
Rock Reptile | 1–3 | -- |
Satyr | -- | 1 |
Snyad | 90% (1–9 on a d10) | -- |
Solar | -- | never |
Spectator | -- | 12.5% (1 on a d12) |
Spider, Huge | 1–5 | -- |
Swan | -- | 10% (1 on a d10) |
Tasloi | 1–4 | -- |
Tiger (all) | -- | 1 |
Treant | -- | never |
Troglodyte | 1–4 | -- |
Troll, Giant Two-headed | -- | 1 |
Turtle, Giant Snapping | 1–4 | -- |
Unicorn | 1–5 | -- |
Vegepygmy | 1–3 | -- |
Vilstrak | 1–4 | -- |
Wemic | -- | 10% (1 on a d10) |
Wolf-in-sheep’s-clothing | 95% (1–19 on a d20) | -- |
Xaren | 1–5 | -- |
Xill | 90% (1–9 on a d10)h | -- |
Xorn | 1–5 | -- |
Chance to Surprise: A creature’s chance to surprise an opponent.
Chance to be Surprised: A creature’s chance of being surprised by an opponent.
-- = normal surprise range.
* Die ranges (e.g., 1–3) are rolled on a d6 unless noted otherwise. Thus, a monster that surprises others on a 1–3 uses a d6 for its surprise roll.
** “Never” means that, in nearly all circumstances, this monster cannot be surprised.
a Only when ambushing.
b Only in natural surroundings.
c Excluding in lair and at night.
d Only when alone and not in metal armor.
e Only in fog.
f Depending on the terrain.
g Only while flying.
h Only when emerging from the Ethereal Plane.
Conclusion
The First Edition surprise rules may be among the most complex in the game. Much of this complexity stems not from the mechanics themselves, but from the awkward and fragmented way they are presented in the rulebooks. Once understood, however, they function smoothly and reveal a system that is mechanically sound rather than arbitrary or overwrought.
Their potential lethality may come as a shock to many players—even experienced ones. A failed surprise roll can shift the balance of an encounter instantly, sometimes with decisive consequences. Yet once the process is clearly understood, it becomes simply another part of play: no more mysterious than any other resolution mechanic, and no more difficult to apply.