here that haven't been
I played until I got to the 2nd boss. Then bored and closed it. Had been wrestling between my wish to give it a fair chance and my wish to not spend time playing the same 4s over and over with no variation, other than during boss bits.
Played it 2nd time after reading in the comments about shooting. But you didn't really seem to explore any of the possibilities that opens up.
+++ Nice, clean gfx. Nothing breaking out of the cute style you've set. Good font.
+++ Quality music.
+++ I really like the musical sfx.
--- It'd be nice if we could turn down the music to better hear the sfx.
--- You don't really mention the shooting in-game.
------ Really repetitive gamplay. In between bosses, we see no change really.
--- Random placement of enemies. Sometimes we have no through-road. Sometimes our failure feels like it should be attributed to the random elements - never a favourable aspect.
overall
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Just way too repetitive and boring. There's a lot of possibilites here that haven't been explored. Work on the level design.
I found it dull and not at all entertaining.