If you feel particularly lazy for some training game, just hold space. You will repeat the mini-game over and over (although with minimal gain per one run)
How to simply obliterate enemies? something with high speed (shinobi/kunoichi/kong-ant) put it into three slots with: stinger, (poison tube/skunk), TNT or something the enemies you hate have weakness to. 4 stinger guys + 2 poison guys + 2 other guys = epic obliteration
the duplicate item bug is still there, and is not as complex as the decribed one in the comments, just save your game, then pick any item you want to duplicate and put it in the "new item" slot, go straight to the skills screen and quit from there, reload and voila: the item is in it's original position and in the "new item" slot
Ninjas are quite easy. Assassins on the other hand are imo, the worst enemies on the last hard levels, since sometimes you get unlucky and nothing can hit them. (not even meteor)
Needs: choose lvl,
lvl unlocking through winning previous one
since when you accidentaly click new game, it erases your progress (which is stupid and made me not play the game again to finish last lvls)
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