Daxter

Let's see, several modes of which I will refer to as "forms", though truth be told, he doesn't really change during battle...

First "form"... Avoid attacks until he comes towards the middle playing field and surrounds himself with a purple-like mist. Once he's within range, nail him with weapon 3. Do this a few times and the terrain changes to allow for...

Second "form"... More avoiding of attacks and jumping from platform to platform. He will shortly fire some shots (delay shots) that take out all platforms at once. When these shots are fired, you have only about 3 seconds to be boosting. While boosting, you may notice a trail of green orbs going on one side of him (right, left, and right for all three cycles of this form). Follow and heat up the coiled valves at the end of them. Do this all three times to bring about...

Third "form"... He'll move around 3 positions. When he picks one to sit on, he fires a delay shot and then begins charging a big orb to hit you with. While charging, hit him with your own orb of blue light and he'll knock out the particular structure behind him. Follow it around when it all stops moving and whack his head with your electrified fly swatter. Do this for all three positions he takes and it's game over for Kaedan. Rest of it is just story.