Eventide is the second set in the Shadowmoor block, which is part of the Lorwyn/Shadowmoor superblock. The two blocks mirror each other in many different ways including flavor and mechanics. Even the expansion symbol of Eventide has striking similarities to that of Morningtide, its counterpart in Lorwyn: where the Morningtide symbol suggests a full sun, the Eventide symbol suggests a mostly eclipsed sun.
Eventide will continue the block themes of hybrid cards and color matters that Shadowmoor started, as well as the Wither and Persist key words. Where Shadowmoor focused on allied color hybrids, Eventide focuses on enemy color hybrid cards. Eventide also introduces two new mechanics:
The Eventide boosters will also include a rules card/token card.
Five theme decks were released as part of the set. The preconstructed theme decks are: "Life Drain" (White/Black), "Sidestep" (Blue/Red), "Death March" (Black/Green), "Battle Blitz" (Red/White), and "Superabundance" (Green/Blue).