Because Mojang has a strict "no distribution of old versions outside the launcher" policy, trading the JAR file is considered grey-market abandonware. However, among private collectors, a verified 12601 minecraft.jar file (with matching hash) has sold for upwards of $400 USD on physical hard drives at retro computing conventions.
It was the very last version before Minecraft transitioned into the Feature Set: It included the minecraft alpha 12601 exclusive
(a silent patch) that existed for only a very short window before the game transitioned to the Beta phase. For over a decade, it was considered "lost media" until it was found in an old backup and uploaded to the Minecraft Archive lost version was eventually recovered by the community? Because Mojang has a strict "no distribution of
Before Herobrine became a meme, Notch experimented with legitimate environmental dread. Data miners have found strings in the 12601 client referencing entity.herobrine.temp and spawn.lonely.tree . Unlike the community hoax, the 12601 build allegedly contained a single, silent trigger: if you dug straight down at spawn without placing a torch, the game would darken the skybox to light level 0 and play a distorted cave sound. The code for this was stripped in the public 1.2.6 release, leading to the claim that the "Exclusive" version is the only one that saw the real Herobrine. For over a decade, it was considered "lost
If you have found a download for "Alpha 1.2.6_01," it is likely a or a fan-made "ARG" (Alternate Reality Game) designed to simulate the horror experience described in the creepypastas. Official archives do not list a "1.2.6_01" version.