You all know about Splash. You all know just how useless Magikarp's signature "attack" is. It does literally nothing but take up time. No status effects, no damage, doesn't distract anybody from anything -- it's even strictly worse than Struggle, meaning that a Magikarp versus Magikarp mirror match devolves to who runs out of Splash first, so that actual damage can be done.
But Sun and Moon's all about that Alolan divergent evolution, right? And even the single objectively most useless "ability" in the game got some love.
All the way at the very end of the clip, you can see that Gyarados received a +3 attack modifier off that single move. Stats modifiers in Pokemon max out at six per stat, and modifiers like Bulk Up or Sword Dance usually increases it one or two at a time at most.
That Gyardos is set to hit harder than the Tunguska Event. Who's useless now?!