Defeat Metal Kor at nest was a mission in Jak II. After Jak finally penetrated the heart of the Metal Head nest and learnt the truth about his past from Metal Kor he had to fight him to stop him from taking the Precursor egg.
The PlayStation 3 and Vita versions of this mission are related to a trophy named "Pedal to the Metal", completing this mission will reward you with a gold trophy.
The final fight and again it exists out of three phases, each one represented by one section of Metal Kor's health bar. Metal Kor has one main attack which is where he fires a blast of dark eco, dodge it by rolling, punching or doing a roll jump. You'll want to watch Metal Kor for when he begins to charge; indicating he will fire.
It is important to note the area does contain crates but they won't contain Vulcan Fury or Peace Maker ammunition, therefore this guide doesn't assume you will have these. Do use them if you do though, even though they're not that effective against Metal Kor.
Metal Kor will release several stinger eggs in the area, you can destroy these before they hatch but otherwise ignore them as they'll distract you from Metal Kor himself. Use the Blaster solely for now and rely on the aerial wastelander move to cut down on Kor and the stingers. If you press the fire button again right after landing you can fire another burst of bullets at Metal Kor which will quickly diminish his health.
Phase two is similar to phase one except Kor will send stingers and wasps as well as fire two blasts in quick succession. The wasps are easily killed with the same Blaster move as before, repeat your previous actions until a cutscene starts.
The last phase of the final boss-fight. Metal Kor will send no more metal heads after you but instead goes after you personally. You'll have to run around the pit in the center to avoid Kor gaining on you, if he gets close enough he'll hit you with his claws and tail. His blast attack now has three shots and he also has a shockwave attack which will cover the entire area.
Dark Jak can finish him off in one attack here with Dark Bomb, but otherwise it is purely a matter of roll jumping away from him, firing the Blaster, avoiding his blasts and shockwave attacks and running away again.