[@Genbor] Hm, could've sworn I put an explanation for that question in the Kurgan Dominion codex entry. But looking back, apparently I've got that information in my OOC WIP. The reason why anti-magic wasn't explored by more nations, was because nobody even knew it was possible or existed. The First Magi's Tome had information on how to defuse mana. The Kurgans secreted away this information and used it to develop the anti-magic equipment that they used during the Kurgan Crusades and Winter War.

Information that I haven't elaborated on yet, is that the knowledge was lost when the Kurgan Dominion froze over, and nobody of Kurgan descent that lives in Waldenkore today has that information. Since Waldenkore is in ancient Altioc's land, the Kurgan Dominion is a long way away. However, the Lorekeepers and leadership of Waldenkore are aware of the First Magi's Tome, frozen underneath kilometers of ice and snow. Expeditions have been led through the Triarchan tundras to attempt to reach the Kurgan homeland, but they have all failed. That said, anti-magic would be extraordinarily helpful against the modern Shotum.

EDIT: Also, welcome aboard [@VoiD]!