Lots of boiling water. For the most part, once boiled, the entire figure goes floppy, and you can pull out the joints and hinges no problem. The shoulder and hip pegs require some grip, so I just used some pliers. The shoulders need to come off first, as the left shoulder peg fits into the neck ring joint to hold the neck on. The hip joints actually peg together.
The ring joints in the lowest leg segments actually seem to not be barbells. Seems the bar running through the ring is actually part of the plastic, so I didn't force them. I assume the same of the wrist and elbow pegs. After that picture was taken I also popped off the bottom jaw section, and pulled out the inner jaw. The dome has two pegs in the front on either side, but once heated up they pop out no problem. There was a tiny dab of glue holding the dome to the forehead, but I gently ran a tiny flat head screwdriver under the dome and carefully pried it loose with no problems.
The head itself is actually two parts, upper and lower, but it's pretty tightly glued. You could probably get it apart with some patience, but I see no real reason to take it apart. The tail looks to be pegged to the torso as well, but it's pretty tight, and, again, I saw no real reason to remove it.