Ikoria: Lair of Behemoths

Mythos of Snapdax | Sorcery | | Each player chooses an artifact, a creature, an enchantment, and a planeswalker from among the nonland permanents they control, then sacrifices the rest. If {B}{R} was spent to cast this spell, you choose the permanents for each player instead. | Seb McKinnon

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

Offspring's Revenge | Enchantment | | At the beginning of combat on your turn, exile target red, white, or black creature card from your graveyard. Create a token that's a copy of that card, except it's 1/1. It gains haste until your next turn. | Daarken

Ruinous Ultimatum | Sorcery | | Destroy all nonland permanents your opponents control. | Chase Stone

Snapdax, Apex of the Hunt | Legendary Creature | Dinosaur Cat Nightmare | Mutate {2}{B/R}{W}{W} (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.) Double strike Whenever this creature mutates, it deals 4 damage to target creature or planeswalker an opponent controls and you gain 4 life. | Viktor Titov

Savai Crystal | Artifact | | {T}: Add {R}, {W}, or {B}. Cycling {2} ({2}, Discard this card: Draw a card.) | Daniel Ljunggren

Savai Triome | Land | Mountain Plains Swamp | ({T}: Add {R}, {W}, or {B}.) Savai Triome enters the battlefield tapped. Cycling {3} ({3}, Discard this card: Draw a card.) | Titus Lunter