Creature - Angel Color tag templates(None) Emeria Shepherd Flying Landfall Whenever a land you control enters, you may return target nonland permanent card from your graveyard to your hand
Legendary Planeswalker - Rowan Color tag templates(None) Will Kenrith +2: Until your next turn, up to two target creatures each have base power and toughness 0/3 and lose all abilities
In addition to those cards I also like Surveilling SpriteSurveilling Sprite, Likeness LooterLikeness Looter, and Faerie VandalFaerie Vandal
There are other creatures and artifacts that also give your swarm +1/+1 counters, additional power, evasive skills, and other ways to ensure that you can put some pressure on your opponents
Xavier Sal, Infested Captain Both populate and proliferate are fantastic abilities that synergize perfectly with fungus-themed decks, as they revolve around adding tokens and counters