Some advice for level 11; a fairly easy level all you need to do is max reset your skills and prioritize archers and mages, then create two full archer towers and one mage tower. For the archer tower set-up I go with Ranger, Mortar, Ranger, so you don't get overrun; for the mage tower just use full-on priests to boost their attack damage. Camp behind the huge fallen tree and just watch as you slaughter your enemies and the huge spider in that level. Enjoy :) hope this helps anyone.
Wow so here's a story, I had upgraded my chance of finding gems to 5% and I thought I should mine something super weak. So I did and I got approximately 50 gems out of it, everyone should try this too it could help.
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