I just wanted to post about this glitch because it should be allowed in All Bosses and 100% if bad stuff happens. It should totally be classified as a Major Glitch though.

1. Hit Aeren until he's almost dead.
2. Run up to right corner until Rubus is also in the top right corner.
3. Run down to the bottom left corner. Rubus's health bar will disappear.
4. Kill Aeren as he runs at you.

There's a video on the Discord if you want to see it. It was posted at 5:41pm on Oct. 1st 2022 in #glitchless