Naya's Challenge

Start with this card in the challenge zone. At beginning of your upkeep put an age counter on it an roll a dice:
1/2 - Deal 3 damage to you and to a creature you control
3/4 - Put X 2/2 Creatures with haste into the challenge zone, being X half of age counters on Naya's Challenge, rounded up.
4/6 - Destroy each non creature, non land permanent you control.