|Primary caster||Fate Testarossa|
|Japanese name||サンダーブレイド |
|First app.||A's (ep.7)|
Thunder Blade (サンダーブレイド Sandā Bureido), a lock-on multi-target attack, is the power-up version of Fate Testarossa's Thunder Rage, wherein compressed mana blades are generated and shot to destroy the opponent with electric explosion. As it does not contain the original binding effect, its physical and magical powers are enhanced.
The blades can detonate on the command phrase "Break!"
- In A's (ep.7), Fate casts it to save Signum from the Scarlet Dragon-like creature.
- In Sound Stage X (disc 2 track 11), Erio casts Thunder Blade with Strada's Unwetterform to deal with 17 units of Mariage in the Marine Garden.