Snorlax

Snorlax is the star: once Mega Hawlucha passes it No Guard via Entrainment, Fissure becomes a guaranteed one-hit KO against every grounded target. Relaxed nature and maxed Defense SP combined with 12 SpD investment make it extremely difficult to KO, and Thick Fat halves damage from Fire and Ice moves, broadening its survivability. Leftovers provides passive recovery to extend its time on field. Smack Down brings flying types to the ground so Fissure can reach them. Stockpile stacks defenses for extended stall games, and Protect provides safety on turns when the opponent goes for a predicted KO attempt.