Voracious Hatchling

Lifelink
Voracious Hatchling enters with four -1/-1 counters on it.
Whenever you cast a white spell, remove a -1/-1 counter from Voracious Hatchling.
Whenever you cast a black spell, remove a -1/-1 counter from Voracious Hatchling.

Evershrike

Flying
Evershrike gets +2/+2 for each Aura attached to it.
{X}{W/B}{W/B}: Return Evershrike from your graveyard to the battlefield. You may put an Aura card with mana value X or less from your hand onto the battlefield attached to it. If you don't, exile Evershrike.