The 12undead_ruins.w3x file you have requested: Maps / Melee Maps / Undead Ruins - 156.86kb is not available. Perhaps try browsing all files for the game Warcraft III: Reign of Chaos and upload any files you want to share or are missing. This is the only information we could locate:
The whole map is full of undead army. You can fight your way to the middle area to buy enhanced undead army or powerful items in the item shop. 1-6players are fixed in locations.