Alarak's beacon is available to Alarak in Co-op Missions. The beacon is invulnerable, and functions both as the way Alarak initially arrives on the field and as the method of which Alarak resurrects himself if he dies. This beacon takes 240 seconds to summon Alarak the first time, then 60 seconds to revive him, unless augmented by masteries.
Protoss Units and Structures of StarCraft II
Versus units and structures
units and structures