Since this is an old version, you cannot just select it from the "Latest Release" dropdown in the modern launcher. Here is how to access it:
If you find a copy, your safest method of play is offline, with your Wi-Fi disconnected, to avoid the launcher "correcting" your files. minecraft alpha 12601 exclusive
A notorious bug in standard Alpha 1.2.6 caused redstone repeaters to flicker asymmetrically. The _01 patch introduced a custom server.properties variable visible only to the original hostโ redstone-delay=2 . This variable was scrubbed from all public source code repositories weeks later. Owning means you possess the only engine capable of reading that original tick rate. For redstone engineers, this is like finding the Dead Sea Scrolls. Since this is an old version, you cannot
For more information on historical Minecraft versions or how to play them today, you can explore the Minecraft Wiki or the GoldenAgeMinecraft subreddit . The _01 patch introduced a custom server
Hereโs a designed specifically for Minecraft Alpha 1.2.6_01 โ capturing that rough, lonely, early-survival vibe while adding something exclusive and strange.