Very neat little prototype that I see has potential! It's hard to give it comments considering that it is not finished but let's do it anyway:

The Good:

If anything, you've definitely got a good choice of music there. It sets up the mood of the game and if you develop along this line, you may find that, maybe scaling up to size is not the 'ULTRA' way to go, but rather speeding up the character may also be a venture to explore.

You've put together a character controller and the rules of his powers of becoming godzilla which is a good start. The jump is a bit floaty so you should look for youtube videos on how to make it not feel floaty. The short answer to that is, game characters fall faster than they rise to give players control in their jumps. This is obviously non-realistic but is an emergent design in games that helps platforming feel good.

As a disclaimer, as opposed to my other comments on the other games, I won't include a "to improve" section as the game is yet to be finished to completely judge. However, I will still suggest that:

Scaling up to size (ie. going ULTRA) is an interesting mechanic, in that I don't remember any game having that mechanic at all. On its own, it feels like a design choice made in isolation but it could be something worth expanding. What if, going ULTRA requires the player to collect ULTRA Food or something, to fill the ULTRA meter - and when it's full, allows the player to go godzilla and kill everything? This way, the game would be more dynamic, and have 2 distinct phase of finding the ULTRA food, then killing everyone before the ULTRA meter runs out.

Nevertheless, that is only one suggestion out of many possible directions you can take this game to. Good one!