@ aloe111 most of the purple towers are end game material and harder to get, after u beat the game on normal mode u will be able to do 250 wave missions (if u beat the game u should be able to beat 200 waves for 4 reward tiers), those missions will have a likely chance on rewarding the top towers. You should be able to finnish the game with t3 mortars (lvl 15), Ice Tower, Curse Tower,t3 Air Guard (lvl 15),t3 Prime Injektor (lvl 15) and Rain of Fire (lvl 25)....if u go on in the main story u will later on get some purple cards as rewards (but the side missions will get harder as well!)
if u do some of the quests wich reward u with diamonds u can buy the 300 diamonds shotgun for the last few lvl. that weapon is just badass so even the final lvl seems piece of cake.
How does it come that enemys with lower lvl have higher hp (about 2-3x) and do like 3-4x times the dmg u do. I can t even do lvl 3 quests as lvl 8 without getting crushed in the final battels in 1-2 rounds.
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