I think what would be very cool is as if there was like a lamp thing floating around in swamps, and the variations from different planets would make it look like something from avatar, or the slylandro from star control 2, I don't think it would be an aggressive mob but I don't think it could be completely passive, like, if you attacked it it attacks you or and eventually runs away. The creature in a realistic stance is a bag of light glowing gas produced from digestion, the body itself it works much like a lung,(maybe that how it would defend itself) with a brain in a hard part of its shell at the top, the brain is probably not very intelligent because the only muscle it has to control is its diaphragm, and its only senses it touch which is adapted to tell altitude, and smell, because it eats methane and oxygen. The really cool thing is that when you tame it, it follows you and emits a glow so you can see a little without a flash light. Hope you guys think this is cool
I'm glad that someone likes this, l will try to post a picture when i figure out how to do that, also, i think that a drop would be the shell on the top which could craft a shield and helmet.
i was thinking for an attack the lamp would spit hot gas at the player, and it would poison him or something