>>30039066I read about how challenging this totem battle was so I was super excited to take it on myself. Interestingly enough, in the pokemon center right before this trial, there is a man who will trade you a Bounsweet for a Lillipup (which can be caught right outside). He even suggests that it will be useful for the upcoming water trial. I made the trade, and in the process of looking for lilipup, i also caught a fomantis. En route to the trial bounsweet evolved. By the time I got to the trial I was able to beat this totem tag team with relative ease using Steenee and Fomantis (the rest of my team was water because im that type of fag).
tl;dr grass is super effective against water, anon.