The user creates a substitute for itself using its own HP before switching places with a party Pokémon in waiting.
Effect
Transfers 1/2 the user's max HP into a Substitute, then the user immediately switches out, and the trainer selects a replacement Pokémon from the party. If the user is the last Pokémon in its party that can battle, if it already has a substitute, or if its current HP is less than or equal to its max HP, this move fails.
The substitute created has HP equal to 1/4 the user's max HP, but is considered the switched-in Pokémon's substitute.
The user may be hit by Pursuit when it switches out, if it has been targeted and Pursuit has not yet been used.