Derelict Falls

Derelict Falls comes into play tapped.
{t}Add a {g} or {u} to your mana pool.
{2}{t}:Sacrifice Derelict Falls and another artifact,
put a mech from your graveyard onto the battlefield.

"Well..... the fish in the pool have three eyes and mandibles. The radioactive shielding on the reactor probably needs work. With some parts.... it could be fighting fit again."