Radagon and Elden Beast in True Oneshot per phase with Giant-Crusher | Elden Ring 

(Patch 1.09.1) Well folks, this was it. This was the toughest challenge that I’ve faced in my history of gaming. Over the course of the past 3 days, I fought this boss with several different builds, almost giving up multiple times because I thought this to be impossible. When I finally realized this strategy, it became apparent that both Millicent’s Prosthesis and the Rotten Winged Sword Insignia will be necessary in order to provide the damage boost needed to complete this oneshot. However, I needed to go to NG+ in order to get both. The good news is that Radagon and Elden Beast both only gain ~20 HP going from NG to NG+, which is easily outweighed by the damage boost gained from having both talismans. Based on this, I believe that NG+ is a must if you want to complete this legitimately. Regardless, I trudged through NG+ with the faint hope that maybe, with both talismans, I might be able to pull this off. That hope was not in vain, as earlier today I pulled off the impossible, killing Radagon and Elden Beast with a single melee hit each.