I think Rollerpig is actually bugged. At one point he abruptly started controlling more like Sonic the Hedgehog -- he needed momentum to get up a good spin and he didn't have the constant momentum he usually does. He was slightly stronger than the chicken. But then something happened (maybe I gained a level) and he was back to his OP self.
Also ... what does "beat the dungeon" mean? I've got to floor 40 with the pig and the past 20 levels had been nearly identical, no changes at all. I'll push to 50, but no further.
Update: Floor 47 was generated with no way to reach the exit (just two tiny rooms). I tried using the right-click cheat to access the only open part of the level I could find, and ended up in a huge room with no platforms and fell infinitely. That not only ended my run, it softlocked the game.
It's sad that a game this promising is so buggy. This is why I hate one-week game jams so much: people rush their coding to meet the deadline, it's full of bugs, and all too often they never go back and polish it up post-jam. Great ideas that could have made for great games, but they're just kind of tossed away because of a contest.