|LEGO® → System → Games → Heroica|
3874 Ilrion is a Heroica set released in June 2012. It includes four bats, three heroes (The Wizard and two new ones, the Prince and the Sage), three new types of monsters (Zombies, the powerful Giant Vampire Bat and the Vampire Lord), a new type of potion and, for the first time, a hostage to rescue, The King of Heroica himself.
In the set there are microfigures for a Vampire Lord, three zombies, the king, three heroes, and two blank gray statue microfigures. The set also includes the Giant Vampire bat which must be assembled. The Giant Vampire bat is strength 4 and has its own health bar. The set looks like most of it is on water, and there are little islands poking up. There is also a jail for the king. It has been confirmed that the set is the catacombs of Ilrion.
Description from LEGO.com