Thunderstone Advance: Into the Abyss continues the story of survival in the forsaken realm. This set showcases a blend of 381 cards from the first six Thunderstone releases, together with some new heroes, spells, items, villagers, and monsters. It also incorporates alternate uses for experience tokens and fourth level heroes for this set and the companion set, Worlds Collide. Into the Abyss is an expansion and requires a Thunderstone Advance base set (such as Worlds Collide) to play.