I tried the "Comunity Challenge" mode last night with Silent (Green) and am surprised that after days of struggling, that combo I used is pretty easy to replicate and win with. I beat the Challenge with 28 cards in my deck, pretty darn easily I might add.
The deck ran on: Back Flip (block 5/8+draw 2), Cloak and Dagger (block 6 + 1/2 shivs), Sneaky Strike (10/14 Dmg, +2 energy if discarded a card this turn), Accuracy (+3/5 Shiv damage), Caltrops (3/5 retribution damage), Concentrate (discard 3/2, gain 2 energy), Footwork (2/3 Dex), Neutralize (3/4 dmg/ 1/2 weak), Leg Sweep (2/3 weak, 11/14 block), Tactician (discard for 1/2 energy), Tools of the Trade (start of turn, discard 1/2 & draw 1/2), and a couple "Attack All" cards as well as a Bouncing Flask (3/4 poison x 3 hits). I also had an Exploding Corpse in there, but only used it ONCE the entire run - and it was often the easy target of a discard.
So LOTS of draw & discard, LOTS of block, and a good number of Shivs. I think that after all my powers were deployed I was cycling through 20 cards, but often played 7 to 10 per turn. I only know the count because enemies were getting Slow (+10% dmg for every card played) and I was getting them up to 70% to 100% bonus damage consistently.