On this edition of "better know an artifact deck" I present a green deck which uses modular creatures and a few combos to exploit +1/+1 counters.
Minion Reflector is a little expensive, but you want it out as soon as possible, because every arcbound creature you copy gets you additional +1/+1 counters for the ones that are sticking around. Additionaly, when an artifact creature is going to be killed, either in combat or at the end of turn due to minion reflector, sac it to the Throne of Geth and you get to proliforate the rest of your army while still moving their counters to another creature. Don't forget, in a pinch you can sac throne of geth to itself for a cheap proliferation.
The biggest combo in the deck is Triskelion and Rite of Passage . With two rites in play, Triskelion becomes an infinite damage/ infinite +1/+1 counter engine. Take off a +1/+1 counter to have triskelion do 1 damage to itself and it gets two +1/+1 counters in return. Just remember, the damage on the triskelion is cumulative until cleanup, so if you build up a ton of counters, then use them all to kill an oponent or a creature the same turn, Trisk is gonna die. It's a small price to pay for a game ender, but keep it in mind if you're playing multiplayer or taking out creatures.
Despite a lot of synergy, the deck is not as fast as most green decks because of limited mana accel, but I think it's pretty resilient once it gets going. Additionally, the game ending trisk combo blindsides many opponents because rite of passage makes so much sense in the deck thematically. If they havn't seen the combo before, you'll probably have to explain why they're taking an arbitrarily large amount of damage to the face.