Here is the full list of all 18 Poker Night 2 achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Win Brock's bounty item.
Activate the Army of Darkness deck, felt, and chips simultaneously.
Unlock all decks, felts, and chips.
Activate the Venture Brothers deck, felt, and chips simultaneously.
Achieve a lifetime balance of one million dollars.
Win Claptrap's bounty item.
Activate the Sam & Max deck, felt, and chips simultaneously.
Activate the Borderlands deck, felt, and chips simultaneously.
Activate the Portal deck, felt, and chips simultaneously.
Win Sam's bounty item.
Purchase a deck.
Win Ash's bounty item.
Purchase a felt.
Purchase a drink.
Purchase a set of chips.
Win a tournament.
Win a hand.
Win GLaDOS's bounty item.