Shared Animosity

Whenever a creature you control attacks, it gets +1/+0 until end of turn for each other attacking creature that shares a creature type with it.

Clash of Realities

All Spirits have "When this permanent enters, you may have it deal 3 damage to target non-Spirit creature."
Non-Spirit creatures have "When this creature enters, you may have it deal 3 damage to target Spirit creature."

Devouring Rage

As an additional cost to cast this spell, you may sacrifice any number of Spirits.
Target creature gets +3/+0 until end of turn. For each Spirit sacrificed this way, that creature gets an additional +3/+0 until end of turn.

Kykar, Wind's Fury

Flying
Whenever you cast a noncreature spell, create a 1/1 white Spirit creature token with flying.
Sacrifice a Spirit: Add {R}.