Player/DM who is having trouble letting go of an old campaign

Question

I'm part of a group of 3 (relatively new) people playing an RPG called Challenger. All three of us are interested in being GM, so we've been rotating; all of our adventures occur in the same universe, but they aren't necessarily connected, so one runs a small adventure in one sitting, then the next runs an unrelated adventure the next week, and so on. However, after playing for a while and getting used to the system, we realized that we were extremely overpowered (really strong loot, and strength in general; one of our players knocked down a castle with one non-critical hit) and started a new universe with more-balanced characters and loot and stuff.

The problem, though, is that one of our players refuses to let go of his old character. He fought to give his character items from before (which we had decided were too powerful for our level), and constantly references and revisits the past universe. He continues to do this despite compromises--we let him make a similar character, and tried to nerf some of his weapons. We all enjoy doing this, and since it's such a small group we can't afford for him to leave the group; what can we do?

Answer 1

The simple answer is the one you've already implemented: Rotate GMs. He has fun with a high-powered campaign, there's nothing wrong with that as such. So long as he's not disrupting the game when it's not his GM night, I don't see the problem with it. Hell, White Wolf made an entire game out of it (Scion), and D&D has some "Epic Level Adventures" supplement or something like that.

I'd suggest asking him what it is about that setting, that power level, that appeals to him... not in order to talk him out of it, but so that you can relate and get into the proper frame of mind to enjoy it on his night. If he wants to basically run an arcade game on paper and dice, dive right in! Be goofy, let it be your night to just unleash and ham it up. You could use it as an opportunity to roleplay over-the-top characters and heroes.

The more difficult answer segues off of that: When you ask him what it is he enjoys about those hyper-powered sessions, try to get to the root elements. Feelings of empowerment, of conquest and success, maybe the glory of being the last man standing... whatever they are, involve them in your plots. I'm guessing you'll find his characters have similar motivations--which is great! You now know what motivates him to adventure, what hooks NPCs can try to use against (or to help) him!