- In general, as Atraxa, Praetors' Voice has shown, Proliferating is stronger than Populating here, both because finding fodder to sacrifice in is fairly cheap and easy to do and because that affects more overall cards. Planeswalkers, charge/oil artifacts, +1/+1 counters, Poison, Energy - all good stuff.
- That being said, I also looked at some of the tricks Chisei, Heart of Oceans pulls off as in many ways yanking a counter off of a card like a Saga or Persist creature is its own payoff for Xavier's second ability.
- One of the strongest things I can think of is populating out more Xavier Sals, so I made sure to include plenty of spells to enable that. It's tough to go infinite that way, and that's fine, but seems like it's a fun and powerful move to do. Populating out haymaker creatures we clone with those same spells or spells like Rite of Replication is also quite good.
Xavier's Bloomin' Pirate Adventure
Approximate Total Cost:
The strong interactions I've spotted (there's a a whole lotta Rube Golbergian 4 or 5 card infinites in here) are...
- Xavier Sal, Infested Captain with a Thornbite Staff can proliferate as much as you can afford to keep feeding him fodder, which can be infinitely with Scurry Oak and is bound only by your mana with Voidwing Hybrid.
- Xavier Sal, Infested Captain can start chaining off if you can clone him with Quantum Misalignment or Irenicus's Vile Duplication and have a Tyvar, Jubilant Brawler. Lightning Greaves, or Thousand-Year Elixir in play to make new copies able to work at hasty speed, especially if you have something like Master Biomancer or Ivy Lane Denizen or Devoted Druid that can continue to generate counters to eat to keep populating.
This deck had a long maybeboard, so interested to see what I missed as some powerful/strong interactions!