Mayvar, Darksteel Forger

Whenever a nontoken creature enters the battlefield under an opponent's control, create a
token that's a copy of that creature except it's an artifact Construct in addition to its other types.
{b}{r}: Target attacking Golem, Construct, or Juggernaut gains indestructible until end of turn.
"I serve you no longer Geth. For all that you are and
own will be mine."