Nykthos, Shrine to Nyx [The List] XY20 Set: EX: Battle Stadium Type:

Set: EX: Battle Stadium Type: Fire Rarity: Holo Rare Retreat cost: Colorless

then shuffles

Set: Jumpstart Type: Creature — Elf Shaman Rarity: Mythic Cost: {G} Allosaurus Shepherd can't be countered

Which tell us the way to go

add {R} for each 1 life your opponents have lost this turn

Nykthos, Shrine to Nyx [The List] XY20 Set: EX: Battle Stadium Type:Set: The List Type: Legendary Land Rarity: Rare {T}: Add {C}. {2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)