Addy steps out from behind a tree, she definitely wasn't there a second ago. "Having fun?"

"Yeah!" She giggles.

"Yay! I've been working on this place off and on for decades now, it's nice when I get to share it with someone new."

"It's really nice! You did good work."

"Thank you."

"What now?"

"Well, you managed to enhance your muscles while climbing that wall, there are harder walls around if you want to challenge yourself in the same way. For more variety there's a somewhat unstable running track in the treetop area. I bet there's some way to challenge any other physical performance limits here too if you have something specific in mind."

"I'd like to try the running track."

"Alright, this way." Addy takes off running straight towards the edge of the cliff. When she reaches the edge an ethereal walkway appears beneath her feet, slowly shifting through a rainbow of colors. Addy is running pretty fast.

River takes off after her, trying to modify herself to run faster - though she's always been good at track, so her baseline's pretty good.

Addy always seems to manage a burst of speed when River is about to catch up. Eventually the ethereal path will merge seamlessly into a wooden bridge, the track here is a bit wobbly as compared to the walkway.

That makes it more fun.

She sees if she can't improve her balance.

There is as Addy said a track, the surface changes from time to time, up ahead there's a segment of what look like giant mushrooms with little gaps between them. Addy bounces higher than might be expected while bounding across them.

Maybe she can do similar by adjusting her leg muscles - and rapidly adjusting how much gravity affects her -

Trying to adjust gravity is much harder than the other things she's tried. Adjusting leg muscles should be pretty similar to what she's already done. When she reaches the mushrooms, she'll find that they are in fact magically bouncy.

Fun!

She keeps experimenting, not being particularly cautious about her own health, but does focus on the race and making herself faster while she's at it.

Addy continues leading the way. The next unusual bit of track has a section with giant lilypads that start to sink into a small pond if you stand on them too long.

Heeee.

She has a lot of fun jumping between them, sometimes taking pretty big risks to avoid standing on one over the time limit.

The worst that can happen is that she falls in. The pond isn't even very deep it goes up to her waist.

Still! She doesn't want to get wet.

Addy is giggling loudly as she runs. When River starts catching up the next time Addy starts adding in cartwheels and forward hand-springs. She's clearly showing off, she may also be cheating but then so is River so who cares.

She tries to enhance herself enough to jump over Addy's head.

She can probably do that but landing might be tricky and the path isn't always the widest. She might end up in a bubble again.

That's okay. She'll just have to keep practicing.

Eventually Addy stops putting on more bursts of speed at that point River can probably overtake her. At that point they're faster than even the best athletes though not by a huge margin.