I liked the idea of scrabble combined with the theme of waves. I also really liked the wave based power ups that you had (although I think that for the game jam, the game should have those enabled by default).
A bit of feedback on the UI/UX of the game:
- The start menu was a bit of a mental overload. Waves going everywhere, large title for the game (good), and a whole bunch of links to different websites. I had to realize that this was the start screen and look for the play button (which I like the theming of btw). I would make the play button much bigger and centered. Then I would anchor all of the links to the bottom of the page where they are not taking up the main portion of the screen.
- Level select screen had a similar problem to the home screen where the waves were very distracting. Maybe if you really want the waves, you could move the spawning point to off-screen and then let the growth of the wave draw the user's attention to the middle of the screen instead of away from it.
- In the main game after moving a couple of times, there are these huge white waves at the bottom of the screen. Other than to try and make the game go with the theme, I'm not really sure of the purpose. I think that removing these would be beneficial to the game because they cover up a good portion of the game board when they are there.