Last updated: 210210…210216
Surprise is elegant—one roll determines both whether the group is Surprised and for how many segments they are affected by Surprise. Dexterity (and other factors) can affect the number of segments a Surprised individual can be directly affected, but only adds or detracts to surprise segments only so far as that individual is concerned if the group was surprised.
A lot of the apparent complexity of Surprise arises from an assumption that a PC with a Surprise modifier (e.g., –3 Dexterity Reaction modifier) can act even though their party was surprised, when their individual Surprise segments are reduced to zero (or below). Yet while the rules explicitly state the surprising party acts, the surprised party is repeatedly prohibited from acting:
- If surprise exists, the surprising party can use the time segments to flee/escape, close, or attack. PHB, p. 103.
- [S]urprise also allows the surprising party to have that number of segments as shown on the die as the surprise factor as free and unanswered activity to move, attack, flee, etc. DMG, p. 49.
- Each 1 of surprise equals 1 segment of time lost to the surprised party, and during the lost time the surprising party can freely act to escape or attack or whatever. If both parties are surprised, then the effect is negated or reduced [referred to as “Lost Segments” in the table]. PHB, p. 102-103.
- A surprised party is caught unawares or unprepared. In such circumstances the non-surprised (or less surprised) party has an immediate advantage which is reflected in the granting of 1 or more segments of initiative, during which the active (non or less surprised) party can take actions A. through H.,)… DMG, p. 61.
- [D]uring the surprise segment or segments, the surprised party is unable to react in any way. DMG, p. 61.
- As party B is surprised for 2 segments, party A has a chance to hit in each segment as if they were full rounds … 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. DMG, p. 71. [Balto doesn’t act due to his Dexterity Reaction modifier, just not be attacked].
- The Dexterity reaction bonus allows the individual “to mitigate” [not remove] the surprised condition. DMG p, 62.
- The Dexterity reaction bonus “adds to existing surprise [segments] or detracts from it”. DMG, p. 62.
So what if PCs can’t act when their party was the surprised, regardless of modifiers? When you don’t make the assumption that members of a Surprised group can act during Surprise, the exceptions that cause ambiguity are resolved.
Process: Each party rolls Surprise. A normal party is surprised on a 1-2 in 6. On a 1, the party is surprised for 1 segment. On a 2 the party is surprised for 2 segments. On a 3-6 the party is not surprised. For creatures that are Surprised on a different range (e.g., surprise 5 in 6), results are calculated the same as those surprising 2 in 6 (except, of course, for more potential Surprise segments).
If both parties roll results in their range for Surprise, Surprise is calculated based on the net of the two results. “If both parties are unsurprised, or equally surprised, determine INITIATIVE for that round.” DMG, p. 61.
Assume A [surprised on 5 in 6] rolls a 4, so it is surprised for 4 segments unless B rolls a 1, in which case A party’s inactive period will be only 3 segments, or if B rolls a 2, in which case surprise will last for only 2 segments (4–1 = 3, 4–2 = 2). DMG, p. 62.
If both parties are surprised for the same number of segments, the net result is no Surprise—move on to Initiative. If one side rolled Surprise for 2 segments, and the other for 1 segment, the net result is that only one party is surprised for 1 segment, with Surprise modifiers calculated for individuals in that party:
- Dexterity: +3 to –3 segments
- Encumbrance: (+1 to +2 segments)
- Alertness: –1 segments
In other words, the number of Surprise segments can be modified –4 to +5. Which specific modifiers aren’t important for discussion, so no need to complicate things by referring to anything but the result, and then examine the extremes. (See https://dnd.sinister.net/im-surprised/ for a detailed analysis of Surprise modifiers.)
Scenario A: Orcs and PCs both roll a 3. Regardless of applicable Surprise modifiers, there is no Surprise, and both sides roll Initiative.
Scenario B: Orcs rolls a 1, Party rolls a 1. Net result neither party is surprised. No modifiers are calculated. Both sides roll Initiative.
Scenario C: Orcs roll a 1, Party rolls a 2. While both results indicate Surprise, the net result is the party is surprised for 1 segment. Applicable modifiers are applied to any individuals in the surprised party, but not orcs.
We have three party members at the extremes:
1. Inactive due to Surprise for 1 segment (default)
2. Inactive due to Surprise for 6 segments
3. Inactive due to Surprise for –4 segments
The orcs have one Surprise segment to perform an action. If casting a spell, the orcs can complete one segment of spell casting. If the spell takes longer than 1 segment, the remaining segment is completed during Initiative (a separate discussion!). Orcs can otherwise take a standard Surprise action. If an orc directly attacks Member 2 (already within 1″ for melee, or a ranged weapon), the orc could attack for 6 segments (don’t get heavily encumbered with a Dexterity of 3!). If directly attacking any party member with no remaining segments of Surprise (i.e., Member 3), the orc’s action is deferred to Initiative.
A Surprised party member, regardless of modifier, still does not act. They’re simply unaffected by direct actions from the other side once they have zero Surprise segments. [This is actually the critical sentence; it’s VERY tempting to say they get to act here, but the DMG says the Surprised party cannot act, and the Dexterity Reaction modifier detracts from Surprise segments, not that it permits acting during Surprise, nor does the DMG or PHB say that modifiers can make them unsurprised.].
Only after everything is resolved for Surprise do both sides roll Initiative, and proceed from there.