A portal appears in random locations, depositing monsters before vanishing again. It will be difficult to pin down without knowledge of the arcane arts that brought it into being.
Unstable Portal
Special Rules
Monsters may respawn at any location as long as they are not within sight of players. When a monster dies, it must point toward the actual spawn point for five seconds before going out of play.
Party
Granted to monsters tied to the spawn point.- Self "Blink 20"
Cleared with...
Dispel, Inspect Magic, or Locate