There are several portals on Earth that lead to parallel worlds. They are hidden from prying eyes and are under constant surveillance by guards who are constantly on duty. This is not a case of the portal opening spontaneously or intentionally from the other side. The hero of the game Repel The Monster is one of the guards, and the portal he was guarding suddenly opened and all sorts of evil spirits came out. Help the guards stop the attack; the monsters must not spread throughout the surrounding areas, creating unrest and wreaking havoc in Repel The Monster.
