Smoke [30th Anniversary Edition] Battle Set: Multiverse Legends Type: Legendary

Set: Multiverse Legends Type: Legendary Creature — Elemental Elk Rarity: Rare Cost: {4}{R/G} Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost

(At the beginning of the upkeep of each of those creature's controllers

search your library for an artifact card with mana value 6 or greater

Even Skyshroud is depleted

but I believe a more mundane power source might suffice

Smoke [30th Anniversary Edition] Battle Set: Multiverse Legends Type: LegendarySet: 30th Anniversary Edition Type: Enchantment Rarity: Rare Cost: {R}{R} Players can't untap more than one creature during their untap steps.