Level 20 is practically impossible to get brilliant. Tons of restarts to make it past 1st smuggler with decent drops only to get wasted by either divers from the pirate ship or 1st Iron Guard. Never enough tower strength or lucky enough to rack up the drops I see on the youtube videos for level 20. Balance seems messed up since I can brilliant 19 and 21 practically on auto pilot once towers are built regardless of drop luck.
we're working on this glitch