Chernobyl

{t}; {e}{e}: Add {b}{b} to your mana pool.
{t}, {b}{b}: Add {e}{e} to your energy pool.
{t}, {2}{b}, {e}{e}{e}{e}: Put an artifact token named Uranium Rod with "{t}: Add {b} to your mana pool." onto the battlefield.
{t}, {3}{b}{b}, {e}{e}{e}{e}{e}{e}, Sacrifice 4 Uranium Rod tokens: You get an emblem with "Whenever you tap a land for {b}, add another {b} to your mana pool."