Here is the full list of all 50 Card Hunter achievements.
Collect all base set legendaries
Collect all AotA legendaries
Collect all Citadel legendaries
Collect all base set epics
Complete the campaign cooperatively
Win 1000 league games
Complete Acquisitions Incoporated
Collect all AotA epics
Win 1000 ranked MP games
Collect all base set commons
Collect all base set rares
Collect all base set uncommons
Win 100 league games
Get MP rating to 1600
Collect all Citadel epics
Collect all AotA rares
Complete an adventure cooperatively
Complete Expedition to the Sky Citadel
Complete Attack of the Artifacts
Collect all Citadel rares
Get MP rating to 1500
Get MP rating to 1400
Get MP rating to 1300
Win 100 ranked MP games
Complete all Basic Edition treasure hunts
Defend Woodhome from the undead
Get MP rating to 1200
Complete a quest
Complete the campaign
Complete all campaign adventures
Get MP rating to 1100
Win 10 league games
Get MP rating to 1000
Defeat Melvelous the Magnificent
Win 10 ranked MP games
Win one league game
Get MP rating to 800
Get MP rating to 500
Collect one legendary item
Find the Loot Fairy
Win one ranked MP game
Find the Hidden Bandit
Save Ommlet from the Kobolds
Complete all campaign quests
Complete all AotA quests
Complete all Citadel quests
Get MP rating to 1700
Get MP rating to 1800
Complete all AI quests
Complete AI hard mode