Combining Metalcraft and Infect? That doesn’t sound very good. Stephen (not Buttons, different Stephen) and Zack have solid Infect decks and I have a Metalcraft deck.
Infect doesn’t really need it; it’s faster than Conscription. For instance, a hand of Vector Asp, Groundswell, Groundswell, Swamp, Forest, Forest means you’ll win on your 3rd turn if they have no answers/blockers.