Surprise is what happens when one side has gotten the drop on the other. The process supercedes the normal determination of initiative, and surprised targets are particularly poor at defending themselves.
A d6 is rolled for each side which might be surprised. Thus if party A is ambushing party B, only party B throws a surprise die. Unless otherwise stated, a combatant is surprised 2 in 6, which means on a 1 or 2 for his side’s surprise die, he is surprised. Some creatures and character classes are surprised on lesser chances, such as rangers (in wilderness), thieves and assassins (in urban areas), and monks above 1st level. In addition, some creatures will increase their opponents’ chance to be surprised (see the ranger for an example.)
If surprise is indicated for any combatant, a surprise round takes place. Only non-surprised combatants can act in this round.
Disadvantages of Being Surprised
Surprised combatants have the following disadvantages:
- stunned (cannot act)
- positive Dexterity modifiers to AC are ignored
- vulnerable to special attack forms, notably assassination and backstabbing, which require the target to be surprised
Surprise and Initiative
If there are non-surprised combatants on both sides of a conflict, then initiative is rolled to determine which side goes first in the surprise round; these initiatives are retained after the surprise round for the rest of the combat, as normal.
If one side is totally surprised, then initiative is determined as normal after the surprise round. It is perfectly possible for the surprising party to win initiative, thus enabling them to immediately take another turn!
Some sample scenarios which may lead to surprise, taken from the Tao of D&D wiki, are listed below.
Surprise may occur when the characters are:
travelling a great distance over the course of a long day, so that if there is no reason to suppose that there may be an ambush being made ready ahead, the combatant’s guard is down.
moving too quickly to properly assess the dangers that might lurk around a corner, so that they rush into a situation before they have time to prepare for it.
attacked in a place usually reserved for peace of mind, trade or goodwill, such as a temple, market, tavern, inn, arena, a busy city avenue, road or square, an upscale residence or a government house, or a heavily patrolled place such as the entry gate to a town or city, a fair or a military headquarters. In such places, combatants will naturally drop their guard, partly due to the number of distractions that makes it impossible to keep their guard up - this makes surprise a possibility, explaining why such areas are busy places for thieves and assassins.
busy with making camp or breaking camp, having failed to establish one person to stand guard during this time, when everyone is moving about and paying attention to details rather than what may be going on all around.
weary, injured to the point where they are in the negatives, drunk, under the influence of a spell or environmental condition, heavily muffled due to the weather, asleep or any other physical condition that would challenge their usual sharp attention.
chatting incessantly in the guise of the players, who are paying very little attention to what their characters are doing, thus indicating that the player characters are themselves allowing their attentions to wander into minutia or frivolity.
expecting one thing but get another. When something comes through the door, over the hill, drops down through the clouds or is stumbled upon that is so completely unusual for the place and time, then there is a reasonable chance that surprise will occur.