Erebus, Underworld Monarch

When Erebus enters, you may search your library
for a Monarch instant or sorcery card and put it into your graveyard. If you do, shuffle one card from target opponent's hand (at random), graveyard, or battlefield into their library.

Once per turn, you may exile a Monarch instant or sorcery card from your graveyard - return Erebus to its owner's hand.