When Foundry Champion enters the battlefield, it deals damage to target creature or player equal to the number of creatures you control. : Foundry Champion gets +1/+0 until end of turn. : Foundry Champion gets +0/+1 until end of turn.
Official Rulings for Foundry Champion
1/24/2013 : The number of creatures you control is counted when Foundry Champion's triggered ability resolves. Foundry Champion will count itself if it's still on the battlefield under your control at that time.