I wasn't able to make the spell remain active after exiting out or carrying it to a new save, is there anything I'm missing? I agree it probably shouldn't be implemented as a strat, but I'm just curious.

Also forgot to mention in the first reply, the glitch only works if you don't have Agility active. If the spell is already active, the mana gets refunded and the spell fails to cast. That happened in my first submitted run by accident lol.

Hey, if anyone is still interested in this, I figured this occurs semi-consistently when casting Agility during lag frames. Most reliable way to abuse this is to use the spell when going through load zones e.g. the bridge to/from Endless Realm, using some setups and just holding W and casting the spell.

These are some setups I could find that work (on my PC atleast)

Both setups on Endless bridge are pretty consistent.

Emberian 2 setup doesn't lag enough to be consistent and is in a short section.

Clockwork catapult setup is pretty consistent. Only problem is you can actually die from taking fall damage doing this setup.

This doesn't seem to save that much time by itself, but it might be useful for saving time on doing less dupes if you can get enough gold. At the very least, it takes some stress and potential time loss away from forgetting to chug potions or cast the spell.

I'm curious if anyone is interested in trying to reproduce this to confirm they work generally and are not hardware related lol.