OK, since there's a majority for three options in particular and I want to get things moving, I'm gonna hurry up and move things on.
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> First and foremost, you really like the look of that dash move. Twelve Fin Slaps runs you through it step by step. Thankfully there are only three steps - look in direction you want to move, imagine yourself flying there, and tap your feet together.
New Ability: Blinking Tide
> You need to work on your charge times, you think. Twelve Fin Slaps teaches you how to better call upon your air, filling up your whistle much fast than usual.
New Ability: Hyperventilate
> For all the awesome your whistle is currently capable of, you think it could use some more versatility. The whip sounds useful - it has range, but it also has some interesting abilities. You can't hurt with it, but holding someone in place with it could be useful, and it seems like the easiest way to take enemies out without killing them - block the gills, make them pass out, then bring them back to the surface for the Breath of Life.
Also, it looks pretty damn cool. That helps.
New Ability: Bubble Whip
> "You fast student!" Twelve Fin Slaps says, impressed. "Though you look like you run out of magic for now."
You're not sure how she figured this out, until you look down and see the dolphin's eye on your chest has dimmed. It must be a sign of how much untapped power you have left, or something like that.
> You offer the master your thanks as your training session ends. You've been here for a couple of hours now, and the dolphins who had surrounded you before are now spreading out to guard the coast.
"No problem!" Twelve Fin Slaps says, saluting. "You make sure to come back when you beat down Champions! Me will come up with new ideas for you and your cute whistle!"
Cute is really not the impression you wanted to give across, but whatever. You return to the surface.
>"Oh, hello again," Shujinko says, sitting on the beach and writing what's probably poetry into the sand. "What did the river dolphin teach you? I assume those boots of yours don't have laces, so she didn't have to teach you how to tie them."
Harami is at his side, glaring him down again before turning to you. "That was fast. I thought you had the look of a quick learner about you. So, what're you capable of now?"