Finally I have done it :D no walkthrough necessary, but level 29 nearly made me gone crazy^^ But after about 50 deaths, I got it (maybe this helps: just make it step by step, there is one little gap right next to the upper spikes)
here an introduction for one endless cave: spawn in sungard, second screen to the right (the one with the bridge), at the top – after entering this sector from the left – between the bushes….just go upwards
I can't understand, why this is a hard badge?! didn't use more than 10 potions, didn't buy one single item, every fight was quite the same...maybe because you have to last a couple of hours to get to the end, this was really hard...
Finally i got this hard badge....My first Try was on September 27th, almost cried because of dying every time at around 290m...came back today, said to me: YOU GET THIS F*****G BADGE! THIS GAME WON'T GET YOU DOWN!..........409m :D sometimes its better to come back later ;)
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 "Snail Bob 4 Space"){kind=icon}
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 "Live Puzzle"){kind=icon}
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 "Psychout"){kind=icon}
 "Legend of the Void 2"){kind=icon}
 "ESCAPE"){kind=icon}
 "Gluey 2"){kind=icon}
 "The Dream Machine - Chapter 1"){kind=icon}
 "Gateway I"){kind=icon}
 "Gateway II"){kind=icon}
 "Reincarnation: A Taste Of Evil"){kind=icon}
 "Crush The Castle 2"){kind=icon}
 "The Several Journeys of Reemus: Chapter 2"){kind=icon}
 "Deep Sleep"){kind=icon}
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