Am I doing something wrong

Originally posted by Sigma-66

The more parts you break the more chances there are for epic stuff to drop. Try to break as many parts as you can before killing.

Full Tempest build should do the trick, but even then it hits so hard that you won't break more than 3 parts if used correctly.

Another thing you could do is freeze the behemoth, making it slower (so it's easier to target parts) using Pangar lantern and Frost weapons (if you don't have Urska legendary yet)