Block traps the target in battle, preventing it from fleeing. It bypasses accuracy checks to always hit, unless the target is in the semi-invulnerable turn of a move such as Dig or Fly. The effect only applies as long as the Pokémon that used it remains in battle.
Ghost-type Pokémon are not affected, nor are Pokémon using Baton Pass, Volt Switch, U-turn or Parting Shot. Affected Pokémon can also be forced out by Roar or Dragon Tail. Block will fail if the target is protected by Crafty Shield.
The user blocks the target's way with arms spread wide to prevent escape.