There is a rather large problem I’ve noticed with bile trolls on legend difficulty. Because they have a large passive healing ability, and the potential to regen to full after being knocked down to half health they can become impossible to kill in some situations where there are only 1-2 players alive. This wouldn’t be so bad except that they also have these really immersion breaking boss gates that make them unavoidable. This has led to multiple situations where the last player alive has to just decide to commit suicide because even though they are still healthy and capable, they can no longer progress the mission because they can’t revive their team, and they can’t kill the boss. This really ruins one of my favorite parts of the game, those edge-of-your-seat moments where 1-2 people are just barely able to pull through. I don’t know how fatshark envisioned the game, but I can’t imagine they’d want to have any regular occurring situation where players are force to just give up on the level instead of fighting it out to the bitter end like the characters they are playing as.
If I were to make a recommendation, it would be to either remove the boss gate (probable not going to happen as much as I hate them with a burning passion), place the boss gate after the team respawn point (kinda like what they did with SpineMangler where you respawn in his arena now), or reduce his indecent amount of self healing.