Not Enough Gems

So I posted a topic on how I’m stuck on Mad Maxer because I have a bad sword, and I don’t have enough gems. see here: Daring Dungeon Rescue
Many people have posted helpful tips, thanks everyone, but I still don’t have enough gems. I am simulating games like mad, and I am also doing the daily polls, but after awhile, you don’t get as much from those. So then I was wondering if there is any other way to get gems without buying or subscribing. Any suggestions?

Repeatable levels, simulating, did you leave any gems on the table by not doing all the bonuses on some level(s), double check to be sure no new levels have appeared in previous regions by looking for the brown/red (no idea which color they are) circles that show a level (also sometimes there is more than one you can do “next”).

That is all I can think of.

edit: check the achievements to see if there are any undone that you could do.