Yeti

The Yeti is an enemy that is encountered near the top of Pesonen Peak. Yetis are the strongest mob currently in the game dwarfing even the bosses currently available in terms of both damage and hit points. Fighting this mob in melee range is not advised as it moves quickly and will often dash towards the player, using a powerful ranged weapon along with exploiting the AI pathing is highly recommended.

Strategy
One method of easily beating the yeti is to kite it a little way down the mountain, taking a hit as it jumps off. Provided it doesn't jump all the way down, when it tries to get back up it will get stuck and can be easily finished off.