みずがため (Water Compaction)

Water Compaction is a defensive ability that triggers when the Pokemon is hit by any Water-type move, immediately raising its Defense stat by two stages. This boost occurs regardless of whether the Water move deals damage, meaning even status moves like Soak will activate the ability. The Defense increase happens after the attacking move resolves, so the initial Water attack won't benefit from the raised Defense, but subsequent physical attacks will face significantly increased resistance.

The ability creates interesting strategic dynamics, as opponents must carefully consider whether using Water moves is worth giving the Pokemon such a substantial defensive boost. This is particularly relevant since many Water-type attacks are special moves, meaning the Defense boost doesn't help against the triggering attack itself, but it does provide excellent protection against subsequent physical assaults.

Water Compaction is exclusively found on the Ghost/Ground Sandygast and Palossand evolution line, which adds another layer of strategic consideration. These Pokemon already resist common physical types like Fighting and Normal due to their Ghost typing, making the potential Defense boosts even more threatening. In competitive play, this ability can turn these Pokemon into formidable physical walls if opponents carelessly trigger it, though the reliance on being hit by Water moves makes it somewhat situational compared to more consistent defensive abilities.