Ikoria: Lair of Behemoths

Mythos of Illuna | Sorcery | | Create a token that's a copy of target permanent. If {R}{G} was spent to cast this spell, instead create a token that's a copy of that permanent, except the token has "When this permanent enters the battlefield, if it's a creature, it fights up to one target creature you don't control." | Seb McKinnon

Mythos of Brokkos | Sorcery | | If {U}{B} was spent to cast this spell, search your library for a card, put that card into your graveyard, then shuffle. Return up to two permanent cards from your graveyard to your hand. | Seb McKinnon

Keruga, the Macrosage | Legendary Creature | Dinosaur Hippo | Companion — Your starting deck contains only cards with mana value 3 or greater and land cards. (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.) When Keruga, the Macrosage enters the battlefield, draw a card for each other permanent you control with mana value 3 or greater. | Dan Scott

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

Emergent Ultimatum | Sorcery | | Search your library for up to three monocolored cards with different names and exile them. An opponent chooses one of those cards. Shuffle that card into your library. You may cast the other cards without paying their mana costs. Exile Emergent Ultimatum. | Zack Stella

Titans' Nest | Enchantment | | At the beginning of your upkeep, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.) Exile a card from your graveyard: Add {C}. Spend this mana only to cast a spell that's one or more colors without {X} in its mana cost. | Cliff Childs

Genesis Ultimatum | Sorcery | | Look at the top five cards of your library. Put any number of permanent cards from among them onto the battlefield and the rest into your hand. Exile Genesis Ultimatum. | Jason Rainville

Song of Creation | Enchantment | | You may play an additional land on each of your turns. Whenever you cast a spell, draw two cards. At the beginning of your end step, discard your hand. | Noah Bradley

Ketria Triome | Land | Forest Island Mountain | ({T}: Add {G}, {U}, or {R}.) Ketria Triome enters the battlefield tapped. Cycling {3} ({3}, Discard this card: Draw a card.) | Sam Burley

Zagoth Triome | Land | Swamp Forest Island | ({T}: Add {B}, {G}, or {U}.) Zagoth Triome enters the battlefield tapped. Cycling {3} ({3}, Discard this card: Draw a card.) | Eytan Zana