Zyclopes are undead cyclopes that are encountered during Eye for an Eye and Final Destination. During Eye for an Eye, they will spawn from near the sun and moon towers and will wander towards various villager's houses and attempt to break in. 27 of them must be defeated to protect the island. During Final Destination, two zyclops are present on the top of The Harbinger and must be killed to reach Captain Cora. Zyclops cannoneers are also present on The Harbinger.
During Eye for an Eye, Zyclops initially spawn with 7,500 life points, but once they are attacked, their maximum life points instantly drops to 4,950. In Final Destination, while the RuneScape Bestiary states they have 7,500 life points, they actually have 15,000.