Create one artifact tailored to each race (for Necropolis, it's the "Necromancer's Amulet"; for Fortress, it's the "Flame Rune" without a bonus to spellcasting; for Inferno, it's the Book of Gorath Raell; the rest need to be invented).
The idea is excellent, but it's important to maintain balance so that these artifacts enhance the races equally.
Added 1 minute ago
+ create an artifact for Engineers.