Step 1: Roll Initiative
When the GM calls for it, you’ll roll initiative to determine your place in the initiative order, which is the sequence in which the encounter’s participants will take their turns. Rolling initiative marks the start of an encounter. More often than not, you’ll roll initiative when you enter a battle.
Typically, you’ll roll a perception check to determine your initiative; the more aware you are of your surroundings, the more quickly that you can respond. However, sometimes the GM might call for another kind of check. For example, if you were Avoiding Notice during exploration, then you would roll a stealth check. A social encounter could call for a deception or persuasion check.
The GM rolls initiative for anyone other than the player characters in the encounter. If these include a number of identical creatures, the GM could roll once for the group as a whole and have them take their turns within the group in any order. However, this can make battles less predictable and more dangerous, so the GM might want to roll initiative for some or all creatures individually unless it’s too much of a burden.
Unlike a typical check, where the result is compared to a DC, the results of initiative rolls are ranked. This ranking sets the order in which the encounter’s participants act: the initiative order. The character with the highest result goes first. The second highest follows, and so on until whoever had the lowest result takes their turn last.
If your result is tied with another creature’s result, then the creature with the greater passive skill score goes first. For example, if a warrior and an orc both roll a 15 on their perception check for initiative, but the warrior has a passive perception score of 15 and the orc only has a passive perception score of 10, then the warrior goes first. If the tied creatures have the same passive skill score, then they can each roll a flat check to determine the order. The creature with the highest roll goes first.
If you roll a natural 20 on initiative, then you gain one free recovery die, which may be spent on exertion (as described under Stamina) without expending any stamina.
Initiative Rush
Sometimes a few points of initiative prevent the cleric from saving the fighter’s life before he makes his last death save, or, if a fighter could move up the initiative order, he could act before the enemy and deal the final blow. When you want to achieve such feats, you can rush your initiative.
At any time between your combat turns, you may announce that you want to rush your next turn. If you do so, you can raise your initiative for this round only by your Dexterity modifier. During your rushed turn you may use only one action.