The Shinnok's Amulet Incident

Raiden charged four gods with guarding the amulet—the gods of Wind (Fujin), Fire, Earth and Water. When the elder Sub-Zero stole Shinnok's amulet from the temple for Quan Chi millions of years later, Raiden appeared before the Lin Kuei warrior and instructed him to enter the Netherealm and steal it back, lest Shinnok use it to free himself. Raiden could not retrieve it himself as his powers would dissipate in the Netherealm. Sub-Zero's mission into the Netherealm was a success and Shinnok was, for a time, no longer a threat. Though it was later revealed that the sorcerer Quan Chi had given Sub Zero a false amulet, Raiden never realized the counterfeit and Quan Chi would remain in possession of the true amulet for years.