How does your submission match the theme?
It's all about balancing mass. If you run out of mass, you die. Everywhere you go, you leave a trail. This takes away from the mass, but going over your trail again takes no mass away. Pressing [grow] twice will make you split. This clone has one half of your mass. If it dies, you get transported back to your previous body. So, on the one hand, you want to have lots of clones so you stay alive longer, but on the other hand, the clones don't have a lot of mass and are therefore vulnerable.

Then there are the boxes. They collect all the mass across the map and put it in one glob. If they are blue, it ends there. If they are red, they also give you the option of a maximum mass upgrade or a refill to your current maximum mass. The red ones turn into blue ones after activation.

Third-party resources
Godot Engine, http://godotengine.org
Piskel, http://piskelapp.com

Contributors
Only me, with some help with the engine from @kidscancode and @YeOldeDM on the godot engine discord.

Source Code
http://github.com/CodeTriangle/glob