Here is the full list of all 18 Poker Night 2 achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Win Sam's bounty item.
Win Claptrap's bounty item.
Activate the Army of Darkness deck, felt, and chips simultaneously.
Win Ash's bounty item.
Activate the Venture Brothers deck, felt, and chips simultaneously.
Activate the Borderlands deck, felt, and chips simultaneously.
Purchase a drink.
Activate the Sam & Max deck, felt, and chips simultaneously.
Win Brock's bounty item.
Purchase a set of chips.
Purchase a deck.
Purchase a felt.
Win a tournament.
Win a hand.
Activate the Portal deck, felt, and chips simultaneously.
Win GLaDOS's bounty item.
Achieve a lifetime balance of one million dollars.
Unlock all decks, felts, and chips.