This achievement requires having Quinn, Lone Wander, a Legendary card from the Defiance set:
This card can be gotten randomly from a Defiance pack or crafted for 3200 shiftstone.
I played against the first Gauntlet enemy with a garbage, likely unoptimized red/green/blue deck consisting of Quinn, several renown units, several ways to draw/cycle cards, some red direct damage (including two of the card that has you sacrifice a unit to deal 5 damage), a relic that allows you to draw a card once per turn for 7, several targeted effects to trigger renown (cheap weapons and buff spells), and four of the green attachment that gives +1/+1 for each justice sigil so I could make large units to dissuade the AI from attacking.
The plan was to try to hold the board until drawing Quinn, then playing her, getting her into the void, using a renown effect to bring her back, and repeating. I did this five times without the achievement popping, which made me think that maybe it wasn't possible in Gauntlet. I then won the match and the achievement popped.