Let's say {Boros keyrune} is in play and I play {march of the machines} can I turn it into the 1/1 with doublestrike after that point?
7/15/2007 If a noncreature artifact becomes an artifact creature this way and then another effect animates it, the new effect overrides March of the Machines's effect. For example, Chimeric Staff is a 4/4 creature while March of the Machines is on the battlefield. If you activate Chimeric Staff's ability and choose X = 5, Chimeric Staff will be a 5/5 artifact creature for the rest of the turn.