A lot of ppl asked me how did I do the arms for Doc Ock. well I'm working on a second one and took pics of the drill holes and arms. I used a 1/8" drill bit in my dremel tool to fit the arms from a Hasbro Marvel Legends series Doc Ock. They are designed to be slid into place with a smaller piece that extends from the tentacle. I drilled a small enough hole so they stay in or I can remove them for storage.