Marath, Will of the Wild Arguably the best commander in Tiny Leaders, Marath, Will of the Wild grows every time you cast it thanks to commander tax, turning +1/+1 counters into real power over the course of a game
Illustrated by Setor Fiadzigbey Standard Not Legal Alchemy Not Legal Pioneer Not Legal Historic Not Legal Modern Not Legal Brawl Not Legal Legacy Not Legal Comp
While cards with a WUBRG mana cost have rarely made any impact in constructed for obvious reasons, there may actually be some potential here
If you want to ascend, cards like Deadeye Brawler are great to put in your deck since they're naturally defensiveand then can start taking control of the game once you've hit ten permanents
And if you're seated at an unusually savvy table, you could always find a way to pump Esper Sentinels stats to make it even more back-breaking
I guess the logic of Undergrowth is that Red-mana creatures can use fire to burn through Undergrowth's effect and still deal damage through the thick foliage