Here is the full list of all 40 Cardpocalypse achievements worth 1,000 gamerscore.
Apply 6 stickers to one card
Change the cards of Power Pets
Win a match with a deck of neutral cards
Change the rules of Power Pets
Complete day 3
Do 30 or more damage in one attack
Complete Mutate-A-Card
Win a match after running out of cards to draw
Play a match where every card in your deck has a sticker
Hack into Mr Leroy's Computer
Complete day 2
Give a great standup performance
Win the Secret Tournament
Complete Create-A-Card
Apply a sticker
Tell on Kyle
Prank Bruce
Win Jacob's adventure
Complete day 1
Win a match without taking damage
Gather a full audience for the Gamatotchi funeral
Let Angelo win
Play 8 cards in one turn
Complete day 4
Complete day 5
Finish the game
Own a common champion for each faction
Own a rare champion for each faction
Become best friends with Yolanda, Cedric, Sam and Ashley
Invite Bruce to join the gang
Complete all sidequests
Tear the Weeniebaby in half
Complete the game in Challange Mode without losing a match
Win a match without playing a minion
Own a 4/4 Tiny Dog
Defeat Cupid... with words
Get ultimate revenge on Colin
Do everything Corey asks and get all of his snacks
Get all of Spud's stuff back from the big kids
Win each battle against the Oracle