Bringer of Green Zenith's [Unknown Event] 088 Set: Grand Prix Promos Type:

Set: Grand Prix Promos Type: Creature — Kor Artificer Rarity: Rare Cost: {1}{W} When Stoneforge Mystic enters the battlefield

Follow one

Set: EX: Hidden Legends Type: Grass

Grown from the seeds of EcoFluxx

and even the Otoko no Michi rules for playing schoolBOYS (albeit mostly delinquents)

Bringer of Green Zenith's [Unknown Event] 088 Set: Grand Prix Promos Type:Set: Unknown Event Type: Creature Phyrexian Bringer Rarity: Common Cost: {X}{G}{G} 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.