the problem with collecting gems is that it is very expensive to use gems to clear levels – unless it’s one of those impossible 6 room scuba diving SWAT team immortal piglet infested type levels…
I have nearly 1000 gems right now and use them maybe once a week to clear a level. I can’t wait to get out of the scuba pig land, only 3 or 4 more levels to go. The gravity world is a lot easier for me for some reason (from Arena).