Thanata, Black Mana Battery

Robotize {4}{b} (whenever this card destroys a creature during the battle phase you may pay
the cost and place a 4/4 artifact creature on your field)
{t}: Add 6 {b} to your mana pool
Thanata wasn't hard at all, A few coins and
some honeyed words and I had my Black mana Battery. - Technaclaw Lab Notes