Ikoria: Lair of Behemoths

Boneyard Lurker | Creature | Nightmare Beast | Mutate {2}{B/G}{B/G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Whenever this creature mutates, return target permanent card from your graveyard to your hand. | Nils Hamm

Chevill, Bane of Monsters | Legendary Creature | Human Rogue | Deathtouch At the beginning of your upkeep, if your opponents control no permanents with bounty counters on them, put a bounty counter on target creature or planeswalker an opponent controls. Whenever a permanent an opponent controls with a bounty counter on it dies, you gain 3 life and draw a card. | Yongjae Choi

Skull Prophet | Creature | Human Druid | {T}: Add {B} or {G}. {T}: Mill two cards. | Nils Hamm

Fiend Artisan | Creature | Nightmare | Fiend Artisan gets +1/+1 for each creature card in your graveyard. {X}{B/G}, {T}, Sacrifice another creature: Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle. Activate only as a sorcery. | Yigit Koroglu

Umori, the Collector | Legendary Creature | Ooze | Companion — Each nonland card in your starting deck shares a card type. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} any time you could cast a sorcery.) As Umori, the Collector enters the battlefield, choose a card type. Spells you cast of the chosen type cost {1} less to cast. | Jehan Choo

Jegantha, the Wellspring | Legendary Creature | Elemental Elk | Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} any time you could cast a sorcery.) {T}: Add {W}{U}{B}{R}{G}. This mana can't be spent to pay generic mana costs. | Chris Rahn

Nethroi, Apex of Death | Legendary Creature | Cat Nightmare Beast | Mutate {4}{G/W}{B}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Deathtouch, lifelink Whenever this creature mutates, return any number of target creature cards with total power 10 or less from your graveyard to the battlefield. | Slawomir Maniak

Brokkos, Apex of Forever | Legendary Creature | Nightmare Beast Elemental | Mutate {2}{U/B}{G}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Trample You may cast Brokkos, Apex of Forever from your graveyard using its mutate ability. | Filip Burburan