Lol. Enter a level, shoot once, press delete and page up, page down all at once. It's funny but you will have to refresh page to fix it as far as i know.
Easy Impossible
Right Click Forward through normal until you get everything and 2 henchmen
Go to main menu then click gladiator mode and right click forward twice
Kill one gladiator
If it doesn't work then right click forward a few times and try again
Repeat as necessary
It worked for me, hope it works for you
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