A move's Priority is a value that decides whether a Pokémon using a certain move will attack first or second. Pokémon using moves with a higher priority will attack before those that use a move of lower priority. Should both Pokémon use a ove with the same priority, the Pokémon's Speed stats will be used to decide who moves first as it normally would.
The list of moves with priority, in their respective priority levels, are as follows:
+5: Helping Hand
0: All other moves not listed
-1: Vital Throw
-2: No moves have a Priority of -2
-3: Focus Punch**
All switches will take place before most moves can be used. The only exception is Pursuit, which will attack first only if the opponent switches out. Otherwise, Pursuit has a priority level of 0.
*- Sucker Punch will fail if the opponent does not attack, or uses a priority move to attack first.
**-The Pokemon will 'Tighten its Focus' before any attacks are used, but the attack itself has priority of -3.
Trick Room will cause Pokémon with less speed to attack first. However, Higher Priority moves will still be used before lower priority moves. The ability Prankster, introduced in the Generation V games, boosts the priority level of all non-attacking moves by 1.
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