Oak is a unique monster located in Pools and Streams.
Defeating him is part of the quest Deal with the Bandits, as he drops the quest item Oak's Amulet.
If you decide to side with him, you win permanent increase of 45 Life.
Abilities
Strategy
Before the fight, be sure to take note of what enemies are at what location. Most importantly, you want to keep good tabs on where the archers are, for they take great damage, and unlike the melee enemies, their damage can't be avoided simply by running away. Usually there are two melee henchmen at the door, followed by several groups standing all standing in a circle with each group consisting of two melee henchmen and one ranged character between the two. One group, however, is just two archers standing by each other. When the fight starts, you should take cover behind the tents.This enables you to take minimal damage from the arrows as well as give you some protection from oak. Oak cannot jump over the tents if you are on the other side. From there you can pop in and out picking off each henchmen starting with the ranged so that you don't have to avoid all the arrows. If oak or the melee henchmen are coming up on you at the tent then you want to simply move behind a different tent. Once the minions are down it is a simple act of attacking oak, running away if you need to heal, and avoid getting hit by his leap slam attack. It is best that you try to bait him into doing the leap slam attack, backing up to avoid, then attacking him while he is still in the leap slam animation and cannot do anything.