Hellfire is an Unblockable Attack used by Steve Fox since his debut in Tekken 4. Ancient Ogre and True Ogre are also capable of using this move in Tekken Tag Tournament 2.
Outside of the main series, Steve also uses Hellfire in Street Fighter X Tekken, where it acts as a short range projectile.
Prior to Tekken Tag Tournament 2, this attack was not categorized as an unblockable, and thus the opponent could attempt to guard it. However, trying to guard against the move would result in the move dealing an unblockable hit that dealt 45 damage with an animation of the opponent dropping their guard and falling to the ground.