Ayara's Oathsworn + Nexus of Fate + Hex Parasite

Ayara's Oathsworn

Nexus of Fate

Hex Parasite

How it works

1. Deal combat damage to an opponent using Ayara's Oathsworn.
2. Ayara's Oathsworn triggers, putting a +1/+1 counter on it and searching your library for Nexus of Fate and putting it into your hand.
3. Activate Hex Parasite by paying 1B/P, removing a +1/+1 counter from Ayara's Oathsworn and giving Hex Parasite +1/+0 until end of turn.
4. Cast Nexus of Fate by paying 5, causing you to take an extra turn after this one, and shuffle Nexus of Fate into your library.
5. Repeat each turn.