Alpha versions were sold for €9.95 (US$13.00 at the time) and were exclusively focused on the Survival game mode. The final official Alpha version, , was released on December 3, 2010, marking the end of this development phase before the transition into the Beta period. There is no record of any version numbered "Alpha 1.2.7" in official Mojang release logs or patch notes. It is the version that never was, a phantom in the update history that has taken on a life of its own.
This version is heavily associated with Herobrine , Minecraft's most famous urban legend. According to the creepypasta, Herobrine is present in this version, and messages like "Herobrine joined the game" appear in chat accompanied by sharp glitch sounds.
To understand what makes the mythical 1.2.7 distinct, let's compare it to the last official Alpha version.
: Traditional block-breaking noises and mob sounds are removed entirely, leaving only a low-frequency, unsettling background track.