Just how does the blood punch work?

[e11]

All I know is that occasionally my glory kills hit extra hard.

[Firaeveus Carron]

When you perform Glory Kills, you fill up your Blood Punch meter (UI above your health), which boosts the damage, range and area of effect of your melee attack. When you fill up the Blood Punch meter to its maximum value, you gain one charge of Blood Punch, which automatically gets applied to your next melee attack. Simply perform a melee attack on an enemy to use it.

[Mexican ground karate]

Also blood punch insta kill pinkes in case you didnt know