Red Witch's Ruby Amulet

Red Witch's Ruby Amulet enters the battlefield
tapped.
{t}: Add {r}.
Rainbow:(As long as one mono-color permanent of
each color is in play, the game has rainbow) Sacrifice
Red Witch's Ruby Amulet: Search your library
for a non-Aura Enchantment card or Sorcery and
reveal it Shuffle your library, put the card on top
of it.
"Stone can erupt with a spell suited to serve a witch's
present fury."