While not as competitive as previously mentioned win conditions, there are a number of draw-trigger creatures that can benefit from windfalls and looting generally, and supercharge by Rielle. Chasm Skulker, Lorescale Coatl, Kydele, Chosen of Kruphix, Psychosis Crawler, and The Locust God come to mind. Surly Badgersaur may be a legitimate option just for the ability to mass-produce treasure when you're doing your thing. Also, it is total overkill, but for strictly humorous purposes Thought Reflection both doubles your initial draw from looting and windfall effects, then doubles Rielle's draw trigger too. That's a lot of cards.
Faithless Looting becomes 1 mana draw four discard two. And wow, Windfall becomes good! (Sarcasm)
4 Rielle, the Everwise
4 Glint-Horn Buccaneer
4 Merfolk Looter
1 Anger
22 Spells
4 Breakthrough
4 Faithless Looting
4 Firestorm
4 Frantic Search
4 Windfall
2 Conflagrate
4 Talisman of Creativity
21 Lands
4 Steam Vents
4 Sulfur Falls
4 Shivan Reef
2 Mountain
3 Island
Figured the best kill would be a Glint-Horn Buccaneer or a hasty Rielle. Firestorm could also be good after a big sequence of draws. Perhaps Reliquary Tower would be good to add? It would make chaining consecutive Breakthroughs absolutely absurd. Also considered adding Tolarian Winds, Dangerous Wager, etc.
Guilds of Ravnica - Commander 2018 - Core 2019 - Battlebond - Dominaria - Rivals of Ixalan - Ixalan - Commander 2017 - Hour of Devastation - Amonket - Aether Revolt - Commander 2016 - Kaladesh - Conspiracy 2 - Eldritch Moon - Shadows Over Innistrad - Oath of the Gatewatch - Commander 2015 - Battle for Zendikar - Magic Origins - Dragons of Tarkir
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