Sunken Slag Delta

Sunken Slag Delta comes into play tapped.
{t}Add {u} or {b} to your mana pool.
{2}Sacrifice Sunken Slag Delta and another artifact,
put a mech from your graveyard onto the battlefield.

"ComStar just left it! A whole functional 80 ton
Mech and they ditched it because it's stuck in mud!"
"So how are we getting it out?"
"Babe, I can't hear you when you mumble....."