Some of the most fun I've had over this jam. Well presented, clean UI, a helpful how to play section (minus some typos, that would bring the level of polish even higher).
My only real comment is about the shop. I don't really understand why there are two different currencies and why you need 10 emeralds to unlock the multiplier that costs 75 gold, it's a bit confusing and maybe could be reworked a bit. Maybe the emeralds could simply be sold for coins and the whole shop worked on coins? Or maybe the emeralds can be used in a secondary shop page for more powerful buffs.
Other than that great stuff, loved it!