Bubble Blast inflicts magical Water damage to all foes or players, also having a chance to inflict Wet status while lowering a certain stat. Its animation and associated debuff have changed between its two appearances so far.
In EBF4, numerous blue pulses appear over the targets, bombarding them with bubbles and hitting them once each. This has a small chance to debuff Attack in addition to damaging and wetting the targets.
In EBF5, Bubble Blast's animation was changed to a swirl of water that forms a large bubble, which floats amid the targets for a second before popping explosively. This hits twice and may debuff Evade in addition to its usual effects.