split panther
The first section can only reasonably be done with the mini cube. It could be swapped for a robot, but there are moments where you hold down after hitting a black orb which is only meant for a cube, so it'll just make those moments unreasonably difficult. Also, there are spaces that only a miniature gamemode can fit through.
Going into the ball section, there's no other gamemode that could do this part. The gameplay solely relies on the balls unique ability of slowly gravity swapping. The swingcopter does this too, but it's a lot slower and its momentum is way higher too, so it would make this part extremely difficult and impractical. The spider can also gravity swap, but it's instant and wouldn't work with the gameplay. And again, smaller spaces don't work well for a normal size.
In the cube, we've changed into a bigger size which is required for this part. I've used lots of yellow pads that bounce the gamemode to a high platform that only a normal sized cube gamemode could reach without any margin of error. The only gamemodes that could do this part without using multiple gamemode portals is ones without borders because the gameplay varies from very high to very low. Using the robot on this part would make this part way harder and it even becomes impossible at one point because of its slightly lower gravity than a cube.
The last part, being the spider, can only be done with instant gravity flipping, which only the spider has. There's plenty of tall walls that are only practical with this gamemode and being normal sized is a necessity because of how far apart some of the orbs are from each other.
hushed marsh
surreal oracle
This exercise can be repeated for extra points.