Create your own artifacts!

Sphere of Absolute Power. Relic. Grants the hero a level upon first placement in the inventory, provides significant bonuses to all stats, and allows the hero to enthrall enemy creatures. If the hero possesses more than one Sphere, the effect increases by a factor equal to the number of Spheres.

Nicholas' Blade. Artifact for the Knight. Allows retraining +10 warriors per week in each city, but -1 to morale. For others, +1 to attack.
Book of Sphere Magic. Artifact for the Mage. Allows casting twice per turn at double the mana cost, but -1 to spell power. For others, +1 to knowledge.
Elven Arrow. Artifact for the Elf. Allows archers to counterattack with an arrow, but -1 to initiative. For others, +1 to archer damage.
Urghash's Key. Demon artifact. Increases summoning from the gate by 25% and increases the number of summoners by 25%. But -1 to speed. For others, +1 to attack.
Ashes' Poison. Artifact for the Necromancer. +25% dark energy, -1 to attack.
For others, +1 to the damage of all creatures.
Hill Sign. Artifact for the Dwarf. Reduces the cost of runes by 1.5 times. But -1 to speed. For others, +2 to defense.
Banner of the Liberator. Orc artifact. +50 rage at the start of the battle, +1 to morale, -1 to speed. For others, +2 to morale.
All effects apply to "others."