The strategy for The Beast is to fire 2 regular right clicks, then fire your first potion shot as soon as he starts doing his charge animation in order to get both potion shots fired in time.

Just came up with a pretty reliable way to one-cycle kill The Sun King as well. If you get the timing down you should be able to do it consistently. It's 5 right clicks, pop ring of mirrors, fire your potion off to hit at the same time the illusions hit with their arrows.

Finally came up with a pretty reliable way to kill Morak in a single cycle. I've been killing off all of his illusions and other enemies, hitting him with 3 regular arrows, then kite the sword until it does the ground slash attack. When it starts, I land a mortar shot directly on Morak and pop ring of mirrors next to him and let it finish him off.

Landing all the one-cycle kills, getting lucky with maze levels, and landing a couple lucky keys from polymorph should allow for times in the mid 42:XX range. With incredible luck in maze levels that might be pushed down below 42 minutes but unless we run into another huge skip I don't think it's really possible to go below 41 minutes currently.

Found a slightly faster way to kill Khamun the other day. It's 2 power shots instead of 5, use ring of mirrors, and fire your ultimate arrow right as, or very slightly before, they fire their first volley of arrows. Your ultimate arrow should hit right as they fire their second volley of arrows, killing Khamun.