I got 14700 ^^. I like that you have a consistent art style, it reminds me of doodle jump. I also think the way your slimes merge while moving your mouse cursor is a pretty fun mechanic, which can increase the skill required as you have to carefully time it.
I do think the game would be better with a minor improvement. Right now if you get a pattern like this:
X
X X
Putting a slime where the X is only deletes either the top or the left, it should be seen as part of the chain, making it easier to fill up gaps.