Just to clarify something—<br/><br/>You guys are entering into an uninhabited, mysterious island where time is weird and it’s chock full of monsters and horrors.  Diplomacy is not something that needs redundance, though something that lets you tame creatures could be extremely useful.<br/><br/>So, technically, if someone could use diplomacy against demons, and someone else can use diplomacy on magic creatures, then that would work pretty well.