Epic Artificer: Achievement PSN of South Park: The Fractured But Whole

After beating the story vendors will sell Artifact Crafting Plans with more than 75 might. Collect the necessary ingredients (after the game you should have more than enough if you looted everything carefully) and craft an Artifact with 75+ might.
There are lots of different crafting recipes. Just buy multiple of them and craft the one you have the materials for. Make a manual save beforehand so you can reload and get your money back.