Resistance 3
59 Achievements
20-25h
Zookeeper
Kill the Brawler in Haven without taking any damage
16.6%
How to unlock the Zookeeper achievement in Resistance 3 - Definitive Guide
This might sound hard, but it's rather easy. The first step to do is to use the Bullseye's secondary fire and tag a part of him, and shoot until it's dead as you back up. As long as you stay far away from the Brawler, he has almost no chance of hitting you.
Just keep up the attack. I was able to kill him just using Bullseye and Magnum. But I also had beaten the game and fully upgraded both weapons. If you don't get close to the Brawler though, you shouldn't have to worry about taking any damage.
Replay Chapter: Haven, OK: Main Street Defense
Once you hit Main Street, you will need to fight off a few waves of Longlegs, Hybrids, and Steelhead. After finishing them off, a Brawler will show up. The Brawler is a large Chimera who deals in primarily physical attacks, however he does launch air few grenades from a distance, and may throw vehicles. To ensure you don't get hit, stay far away from him and shoot him with long distance guns, such as the Marksman. Alternatively, you can get on the opposite side of the central building and shoot through it with the Auger for a fair amount of safety.
In order to damage this beast you need to shoot off his various pieces of armor. The armor which needs shot off will glow orange. Starting with his shoulder guards, to his gauntlets, then chest plates. Tagging these armor sections and shooting them with the bullseye will make short work of them. Shoot these off in that order and the Brawler will go down. If you did this without taking damage, the trophy will unlock. If you took damage, simply reload the checkpoint.
If you'd prefer to follow a video as opposed to text, check out this video by tima022790.
Here is a visual video: https://www.youtube.com/watch?v=4MIBfqi2ERU