The Iron Hall

The Iron Hall enters the battlefield tapped unless
you control three or more noncreature artifacts.
{t}: Add {c}{c}
Whenever a nontoken artifact enters the
battlefield under your control, create a colorless
Gold artifact token with "Sacrifice this artifact:
Add one mana of any color." Then, if you control
four or more Gold tokens, create a 3/3 red Dwarf creature token.