User blog comment:Lord Loss/Monster Appreciation Week: Purple Ludroth/@comment-68.8.97.192-20130401062738/@comment-5963861-20130401102529

The poison theory doesn't hold up really welll, why evolve a defense that could be easily be negated in the habitats they're seen in ??? Another thing to add is that a vast majority of their food is located in water and if they didn't go into deeper water they'd starve. I believe that it was just laziness on Capcom's part to not give it an underwater moveset.