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(Heroes) Marks last for rounds, not turns

Soo... I was seriously surprised that this hasn't been made yet. Or perhaps it has, and I'm just too blind. Wouldn't be the first time. Anyways.
Edit: It seems Cho's Hero Reworks did do this, whoops. Go check it out if you want some spiced up heroes! This mod is just the marks, however. All else is vanilla.

This will make all of the offensive marks from the Arbalest/Musketeer, Bounty Hunter, Houndmaster and Occultist last for actual rounds and not action turns by making them tick down in duration at the start of the next battle round instead of after each action turn, making it a viable strategy against enemies with multiple turns such as the Hag, Crocodilian and Countess.

This only changes the mark duration from these heroes and not enemies nor any self-marking skill.
If you're looking for something that changes all of the vanilla marks to work this way (aswell as some modded heroes as a side effect) this newer version by me will do this. It is recommended that you only use one of these mods at a time and not the two together, as it would be redundant.

Not compatible with mods that makes changes to the marking skill effects of the heroes, meaning it should be compatible with most mods that change these heroes unless they touch the "*** Mark" skill effect.
Does not change mark duration on added hero/class or trinket mods unless they use any of the marking skill effects used by the standard heroes mentioned above.

You can apply this on your own by simply copying the following rule:
.buff_duration_type after_round
into the .effects.darkest file, which was made possible after the patch of May 27th, 2020.