Deeper in!
+1 Try to take the blade and tiny brown bag from the apelike skeleton.
+1, use the blade to try to cut the sap as well.
You get the spearcleaver thing, some sort of foreign weapon from the skeleton. Not your best weapon choice due to size, but weight isn't really a problem for you underwater right now. You try and slice the sap off.
[2]
Nope, this stuff is damn hard. You just need a
slightly better blade. Looks like you won't be using that opposable thumb advantage of yours for a bit longer, in any case.
You also investigate the pouch from the skeleton, taking it and examining the contents. This adventurer seems to have had a bit of stuff, and he won't be using it now.
[5,3,1,5]
In the pouch, you manage to find ten ichorgeld, the unforgeable Cathlan currency, as well as a one-use... fog spell? You Can't quite make out the wording on the officially licensed scrap of alchemically imbued paper. You also find a vertebrae, hardly worth anything... of a coralknight! Wow, those hulking defenders of libraries from ancient times were pretty tough, and most available skeletons have already been looted for the technology and raw magic behing their mysterious creation, so this will have at least symbolic value. Maybe. Alternatively, nobody could care less, you aren't sure, not having listened well in lessons. No weapon, either. What now?