I liked the game and the idea of the two generations. The art was cool but I would go for a constant pixel size. Music was nice. A bit more SFX would be nice as well. That would also help to give the player more feedback on death. Another thing i would improve is to seperate the backround and the level more clearly. Also I would have liked the theme to be more present in the gameplay.
To be honest: For 9 hours this is amazing.