Here he is
Gem: Antozonite. Weapon: Hammer. Special powers: his gem emits an awful stench whenever he's scared or on command after some training.
You can't see it now but his gem is located on his lower back (he tends to keep it covered like Max and Mal). If you're wondering why there are two versions, let me explain:
When Jermy got to Camp Campbell he was the same kid we all know. Chubby, smelly, annoying, etc. But as the summer went on he started to change. He was still the weird chubby kid he was when he got there but he was different. The gem training made him start to loose some weight (not a lot but enough to stop his under ware from showing now that his pants fit right) and he started wearing sneakers to make running easier. Oh, remember that Mal has healing powers? Well, it was mostly an accident, but (similar to Steven and Connie's mishap) Mal unknowingly healed Jermy's eyesight, weird eye infection thing, IBS, and mucusey congestion. So now he doesn't fart as much, his voice sounds less nasally, and he doesn't need his glasses to see (though he still wears the frames because he's so used to pushing them up his nose and such). And there you have it. He's thinner, less gross, less annoying, and most importantly he's still Jermy.