So i've noticed that Trolls are basically a one-hit-death creature, that are extremely lethal and kill you when they spawn. And even with them hitting there chests a bit at first you basically have no way of escaping them since they run at run speed, meaning you have to sit and drink some water to get enough stamina to sprint away. Even then, your probs dead. So i was thinking and hatched some ideas.
First: Levels and toughness.
At level 0 (Cave level, unless that's considered lvl 1 like minehole.) when trolls spawn, they bang on there chests for a good 10 seconds. If they manage to hit you they do a good 100-200 damage. But then they peace and go out of combat once they KO you, like any other non-lethal animal. While your knocked out they'll probs just wander off, so you can TP home. They are around as tough as a boar or deer health-wise.
At level 1, (First Minehole level.) Trolls spawn and bang on they're chest around 6-10 seconds, then attack. When they manage to KO you, they have a small chance to hit you once or twice while your down, but then stop, and if you survived that, they just wander off like level 0 trolls.
At lvl 2 and below they just straight up murder you.
Also, i think Trolls should be seen slowly crawling out of the rock before thumping on they're chests and attacking.