Gate to the Undervault

Description
Build: (3). Invulnerable Deathwatch: Summon a random Demon nearby.

Interactions

 * Invulnerable means it can't die or be affected by anything after it has been built. It can be destroyed before that.
 * Therefore a finished built Gate can't be copied by Superior Mirage.

Balance Changes
v. 1.92 - added with the Immortal Vanguard expansion.