A really good episode on its own, a bad episode in continuity.
Brock (I mean, Dento) did a ton of talking. This was horrific development for Dento b/c he's the EXACT same as Brock in these gym battles. Always serious looking throughout the match, while Iris was playing Dawn, smiling in anticipation. I don't know why it never struck me either until this episode, but Dento is way taller than Ash and Iris-there was one scene where Iris and Ash were shown at about eye level walking, and then Dento walked by, and he was so much taller-his face wasn't even shown; I always remember Dawn and Ash were about the same heights, while Brock was a good deal taller. This episode could just as easily had Brock in Dento's place at the gym, and you wouldn't have known the difference at all-and that's very, very, very, very bad.
The battle itself was pretty good. I liked at how Ash wasn't put off by the attitude change in Aloe's dog pokemon, showing how he was really taking the battle seriously. That's really good. Also the way Piplup's cousin fired water gun (I think that was water gun) was also nice; seemed like it curled a little, which I, using a little imagination, can take to mean Ash has done some training. Not bad. Overall, Ash's composure during the battle was nice to see, except for 1 scene which really annoyed me.
What I didn't like was 2 things. One was where Ash started jumping for joy at how Piplup's cousin managed to defend against the thunderbolt by using its shell. As we saw later on in the episode, if that thunderbolt had landed, it would have been a KO. I don't see why Ash would be excited over dodging a hit that he has to dodge. It's not like him, and it was only encouraging Piplup's cousin's attitude that it's so great-an attitude which I personally dislike, so take this criticism with a grain of salt. Aloe even made Ash's reaction look even worse in how she recognized all she needed to do was get rid of the shell, which she skillfully accomplished. Ash had no plan B (the way he was celebrating, it didn't look like he even had a Plan A; he was never that excited over the moves he worked so hard on in Hoenn or in Sinnoh when he used them in gym battles, and maybe that's b/c he expected those moves to work with all of the practice he put in).
The 2nd thing is my major nitpick with this episode. Why did Ash look so depressed after the loss? Like he had no idea what to do. Hasn't he lost gym battles before? He's always been driven to figure out what to do himself, often doing special training with the same pokemon. He certainly never showed that type of extreme doubt in himself in those episodes (Anabel, Brandon, Roark, Gardenia, Fantina; my favorite one is Brawly, where he was actually upset for losing). I very much dislike Ash's immediate reaction to his loss; he looked sort of like Dawn.
Finally, I really hope this is the end of Ash being overpowered in battles for awhile, b/c it's getting to be too much. Takuto, Shooti, and Aloe make four huge battles pretty close to each other where Ash has been totally overmatched-and seemingly, doesn't mind it too much.