I just read that you said this with respect to Gyarados being water-bound.
But either way TQftL takes place in the anime-verse, rather necessarily what with having anime characters in it, and as far as I've seen in the anime, Water-type Pokémon without terrestrial limbs are always waterbound there. Maybe at some point in the ten years since I started the fic this has been falsified without my knowledge, but it would be rather odd to suddenly switch now.
Personally, I completely understand the decision, although I think as a part-Flying type Gyarados would probably be able to move out of water somehow (even if it can't learn Fly).
Anyway, I found a screenshot from the first movie showing Gyarados and its clone fighting on land:
Here you go.
Just in case you decide to change this in the next revision.
Which brings me to my next question:
After all this time, and given that you've practically finished the ILCOE (which I think is a damn good version), do you still plan to continue with the IALCOTN?