Borderlands is one of my favourite game series. This is an idea a friend and I had for a special enemy. There is flora in the game known as Firemelons (that explode with fire if shot or hit) -  you usually give them a brief look and pass them by. But THIS Firemelon is a badass. If you hit it - it will get moving and lead you to a cave where it cuts loose! Another home and more on about Melonius here.
Looks like a party in there
A couple of items you might get from Melonius