I think it was a good battle between the two. Circumstances aside, such as us randomly going back to 1v1s (Pikachu Vs. Morpeko would have been fun to see) or Gengar learning two brand new moves off-screen, my favorite thing about the episode was how Dynamax was applied. Firstly, Ash didn't immediately react to Marnie's Dynamax with his own - he depended on Gengar's levitation, physiology, and Dark-type coverage in Dazzling Gleam to get by as far as he could (i.e. consuming two of Marnie's turns) until he activated his own on the tail end of Marnie's. Whereas I thought it was to be a kaiju battle of sorts, that wasn't the main focus and I felt it made the match more interesting; between this and Lucario Vs. Machamp, outside of unlikely tanking of super-effective hits, I feel assured that the writers can craft engaging Dynamax fights when they want to. One thing Journeys is getting right is not using Dynamax as a wincon crutch. Which leads to my second point of how both base-form Gengar and Grimmsnarl interacted with and attacked their transformed opponent's; again, I think it makes for a more interesting fight given the relative sizes of the combatants.

We also got to see a full, diverse array of moves, be they Max and non-Max Moves - both Gengar and Grimmsnarl used their entire movesets! I certainly wasn't expecting a Max Hailstorm or Max Ooze! And then to get not just one but both of Grimmsnarl's signature moves along with Poison-STAB for Gengar... And Dazzling Gleam looked simply radiant in its applications. Admittedly, I'll miss Gengar being able to fling Pokémon halfway across the arena with Psychic, but its current moveset is quite good; Sludge Bomb was a surprise, but a welcome one.

And to top it all off, we got the famous forced Marnie smile at the end.

Overall, I liked the episode and Marnie's characterization (she had some nice animation shots too). It's just a shame that Marnie is being introduced so late though, nearly into the series' third quarter; she should have taken Bea's place as a recurring female rival powerhouse. Despite her parting words, I'm unsure if she'll get another battle with Ash within the PWT as things seem to be streamlining towards Raihan, Cynthia, and finally Leon; which is a shame; perhaps a friendly fight outside of it though.

And oh. Most importantly...

OUR BOY FINALLY GOT A CLEAN WIN!