Dota 6.68b should supposed a fix patch for the reported bugs found in the Dota 6.68 Map. However, things are becoming more complicated due to the Uber Chicken Bug and couple of Io bugs that was detected in Dota Allstars 6.68b Map.
Due to this problem, IceFrog has recently released Dota 6.68c Map as a quick fix patch. He had fixed few minor bugs that appeared and detected in Dota 6.68b and also fixed few Io, Guardian Wisp Bugs.
Dota 6.68c Map Download | Dota 6.68c Changelogs