Final Strike is an enchantment added by Thaumic Tinkerer. When applied on a weapon, performing a critical hit on a mob has a chance to triple the damage. This enchantment can be leveled up to level 5 where the higher the level, the higher the chance.
You have formulated an enchantment that enables you to occasionally score critical hits.
This enchantment can be applied on swords. When done so, there is a chance that a hit will do triple damage.