You also may want to get the spike boots to get over the plank, click on the skeletons when exploring upper Sea Caves. ;)

Thx guys,

Time to don my scuba gear again by the sounds of things. I hope I can find the crevasse. got the three things you said I need I think JJ. Not sure if I have those spiked boots, doesn't ring a bell but you never know what I'm carring there somewhere.

I'll let you guys know how I go.

Greyhaize

you can find the spike boot in one of the body in the cave.

note : that's the best boot you can give to RFS-81.