Elden Ring: How to Instantly Kill Malenia (No fight, skip 2nd phase)

It’s “Offhand Stance Swap glitch“, Right hand: any weapon with skill Erdtree Slam (Rotten Staff or Staff of the Avatar) Left hand: Uchigatana and any weapon with ASH OF WAR: GRAVITAS. After swap, holding Weapon Skill button (LT on xbox controller) until boss die.