Vorapede! Not an artifact, but awesome nonetheless.

Vorapede is awesome, but I don't know if my deck could take the triple green...

I myself ran Brutalizer Exarch in my Heartless Lich deck, his implications under Heartless Summoning seem nice, but after a lot of playtesting I found him mediocre, every time I used him I needed him to bury a creature, but that's the one thing he can't do.

Thanks for the tip, Chaosfission. Brutalizer Exarch is out!

Solemn simulacrum is pretty good here too. Gives you card advantage ramp advantage and comes in for just 2 mana. I'd put 2 of them in it.

Nothing else really to suggest. Looks pretty good in general. Obviously something like Grave Titan would be fun, but the deck does just fine without it.

Sylvok Replica is better than Naturalize in the SB as you can recur it with Glissa.

I always enjoy a one-of Surgical Extraction in the board. Wurmcoil Engine is a good card also.

@Emzed - Sylvok Replica was in it originally, but after some playtesting, I found out Naturalize is better because it's at instant speed, and still costs 2 mana without Heartless Summoning. It's just more consistent. But there are some cases where Sylvok Replica is better.

@Millian - I'm making this deck on a budget, so that's why I don't have those cards. Yes, dropping 30+ bucks on a couple of Wurmcoil Engines would be awesome, but I can't justify it right now... but maybe soon!

Wow man great deck for being on a budget, maybe add Life's Finale or Ratchet Bomb +1