Deluge (Big Wave on the SNES and Tidal Wave on the GBA) deals damage equal to 25% of the target's maximum HP. In 2D versions, it is non-elemental. In the 3D version, Deluge is instead a strong Water-elemental ability. It is used by Leviathan, Cagnazzo (as part of the Giant of Babil gauntlet), Ogopogo, and Lunar Leviathan.
The Chill Rod teaches the Illusionist Deluge for 300 AP. The attack deals Water damage to all foes simultaneously and costs 32 MP to cast. It is stealable through the ability Steal: Ability, is also susceptible to Absorb MP, and has a Magic Power of 17.