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. A unique Buy-a-Box promotional card is also considered to be part of the set. Cards with an alternate card frames have another card number than the original version. The Buy-a-Box is #275, borderless planeswalkers are numbered #276-278, Showcase cards are numbered #279-313, and the extended artwork cards are numbered #314-363. The Bundle promo is numbered #364, and the FNM-treatment cards from the universal promo pack are numbered #365-369. Finally, there are Godzilla Series Monster cards that are numbered #370-387. Both regular and foil versions of most of these cards may be found in the Collector Boosters