Summoning Key

Whenever Summoning Key Enters the battlefield,
you may search your library and/or graveyard for
a card named Richtofen, Mad Scientist, reveal it,
and put it into your hand. If you searched your library this way, shuffle it.
{t}. add {b}{b}{b}. use this mana only to cast
Richtofen Planeswalker spells, Artifact spells, or
black spells