By far, the swamp and mountain biomes are the most unforgiving in terms of geographical conditions. The swamps constantly make you wet thus your health regenerate really slowly even when you have the rested buff. Mountain on the other side drains your health if you dont have frost resistant potion/ cape. The mountain terrains also consume a LOT of stamina than usual when you climb upward and regenerates slowly. If you already found Mistland biomes, it pretty much looks like swamp but you might as well turn off your monitor since you cant see anything for how dark it is and I believe it gonna drains a heck tons of uor stamina and health too just to navigates around.