The level curve in this game is stupidly steep. A level 2 dungeon boss/es will obliterate you unless you're over level 10 with better weapons, which are particularly expensive to acquire (real money or being extremely lucky with drops I suppose, if iron ores are found while dungeoneering?)
It's impossible to do the later challenges, simply because having all six guardians out kills the performance due to the bullets thrown out. Don't get me started if they're all shell guardians.
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