chewiepop

Just in the middle of playing through Adventurers club: the presence. Have got pretty far really but I'm stuck in the cave of riddles and I was wondering whether anyone would be kind enough to help me? I've got past the first two pools using the insect egg and resin but I dont know what to do for the thrid one! I figured someone who couldn't get hurt... a dead man? tried the skeleton from the creepy cave and the skull from the ruined city (sorry, have forgotten what its called). Neither of which worked, and now I'm totally stumped! I would really appreciate it if you can tell me which item I need to get past this step.