Cuphead - The Devil Expert Any% - Speedrun 00:54
World record as verified on speedrun.com. Played on Xbox. Exploiting a glitch where you shoot at a hitbox for the Devil that appears offscreen, enabling you to end the fight without ever descending down the hole.
It doesn't appear the hitbox is reachable with lobber/roundabout, so Charge/Peashooter seems to be the optimal setup to exploit this.
Whether or not the hitbox is in the correct position is dependent on what attack is used last by The Devil prior to triggering the next phase. On this run, since the last attack used by The Devil was the 4 bouncy balls, there were actually two hitboxes that appeared offscreen (one to the left and one above). This allowed me to get a few extra hits in to the left before The Devil's skeleton went down the hole, allowing me to save a few seconds.