Ikoria: Lair of Behemoths makes use of monster movie tropes, and is especially inspired by Kaiju (a Japanese genre of films featuring giant monsters like Godzilla). The set is mostly designed bottom-up, but there are also some top-down individual card designs. Monsters are the focal point of the set. Monsters are fighting other monsters, and monsters are fighting humans and their cities. As in Core 2020, the Gainlands appear over the basic lands in about 5/12 boosters.

The set contains 274 cards (111 commons, 80 uncommons, 53 rares, 15 mythic rares, 15 basic lands), and includes randomly inserted Premium versions of all cards.