Water Compaction is an ability unique to the Pokémon Sandygast and its evolution, Palossand. This ability activates when the Pokémon is hit by a Water-type move. Instead of taking increased damage, Pokémon with Water Compaction see their Defense stat sharply increased by two stages. This mechanic turns what would normally be a significant weakness into a strategic advantage, making Sandygast and Palossand more formidable in battle.