Advantage
These were the Dream Creatures of the True Dream Plane.
Upon entering, they were all sent to random locations and even Clarence wasn't by his side any longer. The purpose of these Dream Creatures was both as a challenge and an opportunity.
You were meant to kill them and take the bundle of Dream Force they left behind. This Dream Force was unique in that it gave you access to two paths.
The first path was the path of the creature itself and the second was your own.
To make a complicated matter simple, you could either use the kernel of Dream Force as a conduit to use the abilities of the creature in question, or to access one of your own.
However, there were obviously tradeoffs.
If you chose the first path, you might not be used to the abilities of the Starry Tailed Fox.