A very good take on the theme. Definitely one of the most underrated games in this jam, Nice Work.

The artsyle and music were pretty great, Music actually played a major role as everything was timed to the music.

I did run into some problems though, Mostly just me getting stuck between objects in "white blood cell" stage and "Frog" stage or wouldn't be able to land properly in the "Frog" Stage, causing me to be stuck on the platform until the black void consumed me.

I also noticed that the fail state "Lose when >= 10 cancer cells" never triggered.

Next problem is that the game is very frame rate dependent. Movement, Arrow speed, Jump Velocity and the black void's movement speed increased with increase in frame rate.

This was one of the most unique takes on the theme I have seen, I enjoyed it very much. 

It felt like multiple small games in one and at first I did not really understand what was going on, but by the frog stage it clicked. The whole concept reminded me of the game Spore and how in one playthrough you go through the different stages of life. 

The frog stage was also my favorite stage, although it was the hardest - it almost felt like a full mobile game already.

I dont really have much to critique, maybe the art or the sound could have been polished a bit more but it was also not something that stuck out to me negatively. 

I also like that you used a quote to sum up the whole message of the game, that worked really well. Great job on the whole game! :)