I've had a few affinity builds before and they were fun but had too many colors and never got the fit quite right. This guy looks awesome. Things I see going:
1) He's very very cheap with the right setup
2) He enables infinite combos with artifact creatures, e.g. Ancestral Statue
3) He's in a narrowish color range that should present some deckbuilding challenges
I love +1/+1 counters and I love artifacts. and I really love Tempered Steel!
Some of the cards I'm thinking about:
- Steel Overseer
- Anafenza, Kin-Tree Spirit
- etched champion
- arcbound ravager
- chief of the foundry
- hangarback walker
- scrap trawler
- scrapyard recombiner
- teshar, ancestor's apostle
- thopter assembly
- walking ballista
- Mystic Forge
- Mox Opal
- Ajani Steadfast
- Inkmoth Nexus
- Blinkmoth Nexus
- ancestral statue
- stonecoil serpent
- endless one
The most interesting thing here I think is the opportunity to do a really, really compact ramp package because playing cheap dudes with counters = ramp. But figuring out how to turn that into a payoff is the tough thing, and restocking the hand is also tough.
Some ways to restock the hand might be things like Ranger of Eos and Proclamation of Rebirth, but probably a bunch of things I'm missing.
Congregation at Dawn and stuff that lets you play creatures off the top is probably a very good thing to do also.