How dare the writers not limit themselves to how the games work. At least this time it was natural water instead of a sprinkler.
Yeah how dare the writers not stick to established rules within the anime continuity, just so Ash can conveniently win against a Ground type with his tired electric type Pokemon because the writers couldn't be bothered to put effort into the episode.
Instead of I don't know actually having a realistic outcome, where Pikachu learned Splishy Splash (which would've been foreshadowed), or at the very least Pikachu uses Breakneck Blitz.
Sorry I will never buy "Mudsdale got wet, so it conveniently bypassed its ground typing immunity to electricity" which is only supported by the first generation, but I don't think anyone liked that outcome, since they were being too liberal with established mechanics. As opposed to NOW which they've been more faithful, well up until now.
There's also a difference to say using vine whip to close a Pokemon's mouth (anime mechanics), to just getting wet removing a Pokemon's immunity. One is actually intelligent writing, the other is purely plot hax by the writers because they couldn't be bothered to work within the established rules of the "universe."
Again, Water/ground Pokemon exist, they are STILL immune to electricity........Stunfisk needed to use camouflage to properly be in water, these all happened more recently than Ash's battle with Brock's Onix.
The rest of the comment was okay, but about this, Ash uses anime mechanics like almost every gen
In Gen 1 they did the soaking thing too, in Gen 3 the Thunder Armor(that was the weirdest one), in Gen 4 Ice Jet and Counter Shield, and in Gen 6 Ash Greninja(yes, he started as anime-only)
1. Generation 1 established a lot of stupid mechanics that we're later retconned. They were too liberal (and I don't mean politically people) in generation one, and it didn't work out. Because they could throw anime mechanics into the anime without violating game mechanics, as long as it made logical sense. Vine Whip being used to close a Pokemon's mouth/snout or using vine whip to pick a berry off a tree. As you can easily argue a Pokemon can control the vines and they just don't shoot out of their bodies like "stiff" sticks that cannot be altered.
2. I want to believe the people who are OKAY with this battle, are perfectly accepting of Thunder Armor, since at least Thunder Armor made more sense, if you looked at it as a warped version of "Swellow's Guts" with Pikachu benefiting because of the whole Grotle/Mamoswine energy absorbing thing introduced in DP (which really seemed to only benefit Dawn....which is kind of annoying). Bypassing a Pokemon's immunity feels like dividing by 0. At least "soak" the Pokemon move, seems realistic enough to actually change the typing of a Pokemon, because that's what it was designed to do, don't think "NATURAL" water has the same effect otherwise ground types wouldn't be so deathly afraid of water.
3. Ice Aqua Jet made sense, given how Aqua Jet was portrayed, the only issue in believing it would work if a Pokemon would be able to survive aqua jet being frozen over
4. Nothing in the game really contradicts Ash-Greninja, given that Ash-Greninja was actually designed by Game Freak, it further is perfectly fine with me plus I'm fine with the anime taking liberties like this, especially since they actually went to Gamefreak and asked how they could make Ash's Greninja special. Basically they went out of their way to get approval from gamefreak, as opposed to doing whatever the hell they wanted.
I'm NOT AGAINST anime mechanics, BUT they have to make sense. A ground type losing its immunity to electricity just because it got wet seems like a complete contradiction of the natural order of things within Pokemon, because otherwise, ground types should be vulnerable to electric types just by jumping in the air, since the only reason they'd be immune is by dispelling the electricity in the ground. But when has a ground type taken damage from electric attack by flying.
Pretty sure I remember Gligar and Gliscor "flying" and they were still immune. So how does getting wet make any logical sense to bypassing the "immunity" since getting wet is not the same thing as a Pokemon move like Soak.