Bringer of Green Zenith's [Unknown Event]

You may pay WUBRG rather than pay this spell's mana cost. If you do, X is 5.

Bringer of Green Zenith's Twilight enters the battlefield with X +1/+1 counters on it. If X was 5 or greater, it enters with twice that many counters instead.

When bringer of Green Zenith's Twilight dies, shuffle it into its owner's library.