>>44706721You can teach Grapploct more water moves, but it doesn't learn all any of them without training. The potential is there, but it doesn't inherently produce them. In fact, its natural move list only includes Octazooka, a nod to the animal that it's based on, which it only learns by move re-learning.
Interestingly, its pre-evolved form, Clobbopus, can't even learn Octazooka.
Also, "octopuses" is a perfectly valid plural for the word "octopus," but that's not really important.