Subterranean Colony

Defender, swarm.
Sacrifice a token creature, {3}{g}: Create a
pheromone enchantment token with, "Whenever
you cast a creature spell, amass Insects 2." Only
use this ability if you don't control a pheromone
token.
Sacrifice a pheromone token: Add {1} to your
mana pool. Only use this mana to cast
non-creature spells.