Phenax, God of Deception + Sewer Nemesis + Maddening Cacophony

Phenax, God of Deception

Sewer Nemesis

Maddening Cacophony

How it works

1. Cast Maddening Cacophony with kicker by paying 4, causing the opponent named by Sewer Nemesis to mill half their library, rounded up.
2. Activate Sewer Nemesis by tapping it, causing the opponent to mill cards equal to the cards in their graveyard, milling the remainder of their library.