Mental Magic (5G)
Defeated Jace
this achievement will be unlocked as you progress through the campaign.
After completing second plane in this campaign; Theros, then you will move on to the third plane: Ravnica. Here you will need to beat the following missions in this order:
Search The City
Orzhov´s Demand
Selesnya´s Power
Jace´s Test
When you win Jace´s Test you will get this achievement.