You can cloak anything with Vannifar, from spells to lands, effectively preventing you from ever having a dead draw
That gives you some room away from big scary creatures for at least a turn, letting you push back any devastating attacks and/or clearing some runway to get damage through
High Troller generates ludicrously swingy board states, which is exactly what some Commander players love to do (and I had a blast losing to it in a protracted board game where it survived by ludicrous variance and eventually killed me)
Its fast, strong, and versatile, and it punishes your opponents pretty strongly
So, it really doesnt take long to overrun your table with these cotton-tailed combatants and to add even more tokens to airborne Zinnia
When those decks are good in the meta, the spirits player can often win the next turn after a chains