Horizon of Darkness

It won't disappear; it will simply trigger again when it drops below 80% next time.

I mean, there might not be a free heal... Oh well.
Is the number of slots in the post with the players still accurate? Then...

Nikta deals lethal damage to rat 12
Fai casts WSH2 on 11
Zeikin uses Cleave 2 on 1 target (any, preferably not wounded)
Henry jumps 2 on 9, if alive, otherwise auto-attacks any
Joe, if rum takes effect in the next battle (it's not clear from the description), drinks. Otherwise, he drinks anyway, because a Heroes player needs to role-play the character, and he hasn't had a drink in several battles. Level 2.