You can hug the top rank to get queens often, since your pawns come pre-equipped with upgrades. Obviously cantrips are the best, but splash attacks come before shields because they help you clear nimble enemies much faster and killing multiple blightsacks at a time will limit the blight to an area and you can use another move to get away. Shields are still mandatory in the gauntlet because the shaman champion is always there. you can't always stay next to him so you have to tank a hit every turn. Stacking a knight with splash and cantrip is useful because there is a certain gauntlet spawn that allows you to kill 2 nimble enemies in one move. Bishop cantrips are underwhelming for their high cost. Stacking upgrades on a few units is better than spreading them out. It's better to hope for better draw rng than get cornered because you clear too slowly. You can only play two cards a turn(not counting cantrips); you want as many effects for those two moves as possible.
Finally became a Dungeon Grandmaster after much resetting. There's not too much advice I can give besides "get lucky". There is so little room for error in the later stages that it comes down to draw rng and how kind your shops were to you. The game is slick to look at but it's too shallow to justify tearing your hair out for the impossible badge for most sane people. It's a shame that the last impossible badge on the site is for something so dependent on luck. There is strategy in the game, but for the impossible badge in particular to deal with the horseshit in the gauntlet you need to have certain upgrades and not draw 3 duds in a turn since one turn on the wrong tile can mean instant death.
I really like this game, but premium content (or paid DLC) in anything but the largest blockbusters will result in people complaining about how it's "not worth their money". (*cough* Black Ops DLC) Unless you're aiming to sell this at retail price, the internet is going to whine.
Congratulations! You just won the No Challenge Badge and 30 points! I love the story and weapons - 5/5. to beat the dudes in suits I had a chainsaw level 6 with rear of metal and spam the barrier and teleport to the falling health boxes.