factory glue

All of the above are very good, and when boiling and prying together won't work for me, I tend to use a 3 step process, boil the figure, then use the screwdrivers to wedge open what I can, finally, with the figure still hot and pliable, use an Xacto knife with an APPROPRIATE blade for the area and angles you are working on to "encourage" additional glue separation, and in some cases to encourage plastic insert separation. You cut while you can and continue to pry. When the toy has re-hardened enough that prying is difficult, it's time to re-boil.

##DISCLAIMER #1 ##
Use of an Xacto blade, or any other sharp object should only be done by an responsible individual or under the supervision of a responsible individual. Failure to follow this can cause, amongst other things, breaking of your blade, premature dulling of the blade, and personal injuries, both puncture and incision(poked hole or cut). Please always use tools responsibly.

##DISCLAIMER #2 ##
Boiling water is HOT, and can result in burns. Please ensure that no boiling water will contact your skin or you may be burned.

##DISCLAIMER #3 ##
While useful, this technique takes practice and patience. There are no kerf losses to the use of the blade, as there would be with a dremel, however, the cuts do tend to be a different texture than is wanted for the final figure, ensure you can reproduce the textures you want.

just don't immerse the hairdryer in the water! remember safety first!!

Heat usually works. Try boiling water or the hair dryer. That's how I get off attached pieces like capes and pouches and punisher skull teeth.

I get those cheap tiny hobby screw drivers at the dollar stores and wedge in whatever will go, starting with the tiniest and just PRY! Usually it gives in about 5 minutes!

don't think the dremel will work. I don't want to harm the inside head

sometimes just emersing it in boiling water you can prize factory glue apart

failing that - Dremel!!!