Maelstrom of Darkness

Maelstrom of Darkness enters the battlefield tapped unless you discard a black card.
Black spells and abilities you cast and activate costs {b} less to cast and activate.
{t}: Pay 2 life. Add {b}{b} to your mana pool. Use this mana only to cast black spells and activate abilities of black permanents you control.
{t}: Add {b} to your mana pool.