Buying the Sanctum of Domination Mythic loot run is the only way to boost your character’s ilvl to the maximum. The second fated mythic raid of Shadowlands will allow players to get powerful 304-311 item-level gear, and achievements for killing 10/10 available mythic bosses.
Fated SoD mythic boost is available when this affix is active in Sanctum of Domination.