Helm of the Host (Promo Pack) [Dominaria Promos] RC5 You'll also need the Killzone:

You'll also need the Killzone: Bheta-Decima terrain set to create the mission maps in the book

where X is the number of other Elves you control

Set: Rise of the Eldrazi Type: Creature — Hydra Rarity: Mythic Cost: {G}{G}{G}{G}{G}{G}{G}{G} This spell costs {G} less to cast for each green creature you control

Set: World Championships 2009 Type: Psychic Rarity: Rare Retreat cost: Colorless

Helm of the Host (Promo Pack) [Dominaria Promos] RC5 You'll also need the Killzone:Set: Dominaria Promos Type: Legendary Artifact Equipment Rarity: Rare Cost: {4} At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary if equipped creature is legendary. That token gains haste. Equip {5} Forged out of flowstone for the queen of Vesuva.