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