So, Olivia basically set Ash up and made Mallow a part of it, which explains why Mallow didn’t do much at all in this episode. She was just basically there to guide Ash and make sure he made it to the Trial (at least that’s what it seemed like to me). I personally would’ve liked to seen Mallow do something else, but this Trial ended up being just about Ash, so I respect the decision made by the writers. I also assume that Olivia did this to basically test Ash, before she faces him in the GT, so it makes even more sense as to why Mallow was not really involved. A couple other things I liked was how Ash remembered and used Rockruff to find his way out of Diglett Tunnel, basically not forgetting about Rockruff and his natural abilities. I have to admit, that I was laughing with everyone else when Ash slipped and twirled in the air.
As for the battle, it was average. Not bad, but not great either. I did like how Litten and Rowlet were working together, especially when Rowlet picked up Litten, and also how Rowlet KO'd the Castform (was kind of funny from my perspective). Litten actually looked good int his battle and I'm real glad that it did and also used a Z-Move to KO the Totem Lurantis. Oh, and Litten getting hit with the Water Gun attack was funny (Litten's reaction).
Another thing, concerning this battle, I don't understand why some people are criticizing this Totem Battle to the degree that they are. I mean, one has to remember when watching these Totem Battles, you can't compare them to gym battles or to that degree, because Ash and others are facing a wild Pokemon, not a Pokemon that's being controlled by a Gym Leader. Now, one could argue that since these are Totem Pokemon, they should have experience in battling, which they obviously seem like they do, but it's not going to be to the degree of a Gym Leader commanding his or her Pokemon, which also can drag out an episode longer (trying to come up with a strategy mid-battle or a counter move, dialogue, substituting/using multiple Pokemon, etc..) So, a battle vs a Totem Pokemon, only lasting for half an episode, DOES make sense.
Anyway, I do wish that Mallow would've gotten something from this episode, but I understand why she didn't (from the episode's plot). Ash gets another Z-Crystal which is always cool and it looks like he's going to be using it quite soon. Good episode I guess, but nothing too special.