Experiments are creatures created by Dr Fenkenstrain. They consist of two different species in a single body. They reside in the experiment cave, located underneath Fenkenstrain's Castle, and consist of 7 sheep-dogs, 5 spider-men, and 6 wolf-women. Partial completion of Creature of Fenkenstrain is required to access and kill them. The wolf-woman must be killed during the quest to retrieve the cavern key, but cannot be killed after the quest. Attempting to do so will generate the message "You don't have the heart to kill the poor creature again." This restriction does not apply to the sheep-dog or the spider-man experiments.
Killing an experiment is required for the easy Morytania achievement Lab Clean-up Assistant. During the Rag and Bone Man's wish list, they drop an experiment bone.
- Universal drops are dropped by nearly every monster outside of Daemonheim.
- These items are dropped alongside main drops.
- The sheep-dog experiment is a reference to a sheep dog, a breed of dog used to guard livestock.
- The spider-man experiment is a reference to the Marvel superhero Spider-Man.
- Before the Evolution of Combat, experiments were a very popular training method because they had 1 Defence, max hit of 1 and had 1000 life points.
- Experiments still use the old sounds for wolves and spiders when in combat. Additionally, they use older graphics for their models.