It is important to clarify upfront that as of my current knowledge (and the latest updates from Blizzard Entertainment), there is no official "Warcraft III: Complete Edition" labeled with the version number "V126.0.6401a" circulating through legitimate, authorized channels (such as Battle.net).
Connectivity Fix: Addressed a bug that caused Mac players to disconnect frequently during Battle.net games. Warcraft III - Complete Edition - V126.0.6401a ...
Players often seek out V126 because it does not require the modern Battle.net launcher or an active internet connection to play offline. It is commonly found in community-made "repacks" (like those by ElAmigos) that bundle the entire experience into a single installer for easier setup. Warcraft® III: Reforged - Battle.net It is important to clarify upfront that as
The battle that followed was less a clash than a conversation in which both sides spoke in blood. Charges collided with the brittle clap of bones. Mirelle wove through fight with a stoic rhythm, her small knife opening a path. Vel’Gor fought like a mountain whose path was anger. Joruk, throat ragged, held a broken spear with a faith that surprised them all. The child, hidden behind the wagons with the music box now returned—found and clasped to her chest by a stranger—hummed the cracked lullaby, and something in that near-forgotten melody bent the edge of the world. Registry Edit Method (Manual):
“Vel’Gor,” the larger one said, naming himself as if that settled anything. “Hungry time. We look for food.”