Found a nice secret near the end game! After becoming the Number 1 Mage keep talking to the Mysterious Hermits in "Bar & Marketplace", after some interactions he will reveal himself as the actual strongest Mage and fight you! It's pretty hard and I'm not sure if he's beatable, but it's there :D
Just warning guys, about the Easy Badge: I've killed 3 pterosaurs and a bat during the superman, but no badge, tho in another play in superman as I hit a Hornet (or bee or whatever) I got the in-game achievement and the Badge. It's probably bugged. Maybe it helps.
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 "Flood Runner 3"){kind=icon}