Dwarven Mine
The Dwarven Mine is located north-west of Falador . Home to two Mining Shops, a general store and at least one rock of every known minable substance except limestone, runite, quest only ores (like blurite), gem rocks and silver, the huge mines are a miner's dream- just watch out for the scorpions in the lower half! The mine also features a secret "back exit" to Falador, and an access gate to the Mining Guild.
Now leave the castle again, but this time follow the path to a small graveyard to the southeast. Use the Star Amulet with the Memorial to the far east, and then Push it to find a crypt. Follow along the path into a room of Experiments, and kill the level 51 Experiment that appears to be both Wolf and Human. Pick up the Cavern Key that it drops and continue northwest along the twisty path until you come across a gate. Unlock it with the key and head up the ladder, to find yourself on a small island with 3 memorials to the north. Dig in front of each of them to receive a pair of Legs, Arms , and a Torso.
Push the Memorial to the south and make your way back through the cavern, to the Hair of the Dog Tavern. Talk to Roavar and ask for something to eat. Buy the Pickled Brain for 50gp, and use it with the Decapitated Head. Bring everything back to Dr. Fenkenstrain, who now needs a Needle and 5 Thread to sew the parts together.