This booster set features the girls from Lyrical Monasterio in their Halloween costumes. It showcases Fortia and Herminia from Lyrical Booster Vol.2 (see "'Lyrical Booster 2'"), and players can build decks from three new ride lines in this set. The set has 94 types of cards: 16 types of RRR, 1 type of ORR, 19 types of RR, 21 types of R, and 27 types of C. There will also be parallels included in the set. Boxes come with 16 packs, and each pack has 7 random cards.

Lyrical Monasterio: Trick or Treat will also have a Sneak Preview Kit for preview events. The kits come with 47 booster packs, 8+1 promotional cards, and 2 premium rubber playmats.