Essential Material: Thunder Feat (Patreon)

The penultimate technique of the martial arts of the ancient Celts. A technique of such lethality and power that it was only ever surpassed by the Gáe Bolg, the secret technique of Scáthach and Cúchulainn. It was with this technique that Cúchulainn slew one thousand warriors without effort.

There are many forms to this technique. It may be accomplished with numerous tools, for the method of delivery is irrelevant to the technique itself. However, the primary and most basic form of this technique utilizes nothing more than the bare fist. Cúchulainn wielded it using a sling.

The characteristic sound of this technique is what gives it its name — with a sound like thunder, the user unleashes his power and obliterates the enemy. 

This is a technique that can only be learned at a certain level of mastery in the ancient Celtic martial arts. It is only once one has conditioned his body, mind, and spirit to a sufficient level that he can wield this technique.

When pushed to the maximum at the highest levels of mastery, it is even possible to slay gods with this technique. That is to say, the fabric of space and time is warped such that to be struck by the Thunder Feat is akin to being hit by a white dwarf star moving at the speed of light. A punch with infinite mass, you might say.