Thunder Slash is a Sword Art used by Steiner that is supposed to deal Lightning-elemental damage to a target for 24 MP, but due to a glitch it misses almost every time. Thunder Slash can be learned for 30 AP from the Defender and Ragnarok. Thunder Slash will never work on bosses. The ability is also part of Beatrix's Seiken command.
The damage formula is:
- $ Damage = [19 * Target's Max HP / 100] $
Thunder is the sound caused by lightning. Depending on the distance and nature of the lightning, thunder can range from a sharp, loud crack to a long, low rumble (brontide).