Great work!
I expected another lame memory game but this took me by surprise.
All the upgrades and the hint of a story actually made it quite compelling.
The art, sounds and animations were really good too.
The only thing missing here is medals. That would make it perfect. I still haven't rated the submission. Add medals and you shall have your 5. :-D
By the way, I'm playing it on Chrome as well. It took me about 5 minutes to get the game to load but it was worth it.