Hex Parasite + Kheru Bloodsucker + Vorapede + Pitiless Plunderer + Altar of Dementia

Hex Parasite

Kheru Bloodsucker

Vorapede

Pitiless Plunderer

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Vorapede.
2. Vorapede dies, triggering itself, Kheru Bloodsucker, and Pitiless Plunderer.
3. Resolve the Vorapede trigger, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
4. Resolve the Kheru Bloodsucker trigger, causing each opponent to lose 2 life and you to gain two life.
5. Resolve the Pitiless Plunderer trigger, creating a Treasure token.
6. Resolve the Altar of Dementia ability from step 1, causing target player to mill cards equal to Vorapede's power.
7. Activate the Treasure by tapping and sacrificing it, adding 1.
8. Activate Hex Parasite by paying 1, two life and removing the +1/+1 counter from Vorapede, giving Hex Parasite +1/+0 until end of turn.
9. Repeat.