LMAO, good ol Gurren Lagann.
I wasn't expecting the actual mecha to show up but that was hilarious! Well done!
I'll only rate it 4.5 stars because it could have used a little bit more thought into the logic of Gurren Lagann showing up. For example, there could have been something like a flashback where we see Squirtle somehow being able to buy something from a store and, you can't quite tell what it is cause it's blurred due to 'camera focus' but you can see enough to recognize that it's Lagann. Back in the battle, Squirtle could then be seen 'equipping' Lagann, revealing Gurren hiding in the tall grass, did a 'joke' evolution where Lagann evolves into Gurren Lagann and then used the Horn Drill attack. I dunno, that's just something I came up with. It just needed a little bit more to tie the wackiness together.
(I do find it rather interesting that some people are literally clicking the link of a pokemon parody just to type "Oh look, another Pokemon parody" and yet...this is Newgrounds. There's a reason it and many other popular franchises have their own categories. If you don't like them, don't click on them just to write a review that complains about their mere existence.)