Hi InsightInc. I'm sorry for the late reply.
For the random split, I think it's a bug. It should be only splitting after jumping once, get hurt by enemies or falling out of the game area. For the game stuck on not predefined game area, is it because the split and combine of the slime that occurs infinitely? Or just falling infinitely? I think I'm still not implementing the game border very well. And, thanks for pointing out the jump/move speed. I still don't know how fast/slow it should be. So, it really help me for improvement. XD
The game itself is still full of bugs and is not yet completed because the time limitation. I'm sorry. But, I will try to add and fix some things later.
Thanks for the review XD