This is a 2-part boss fight, the first part is killing Lockmaw, the second is killing Augh. You can do both of these separately, so for that reason pull the croc back a bit so that Augh doesn't aggro right away. (you are out of combat until you pull Augh). Avoid clouds of dust. These spawn where Augh whirlwinds and where Lockmaws tail is. They cause massive, avoidable damage. Augh has a presence in phase 1, but is easily avoidable. Dont get into his whirlwind and you should be fine. Around 40% or so he will go into a venomous rage, and this can should be tranq'd or soothed off.