Here is the full list of all 50 Viva Piñata: Trouble In Paradise achievements worth 1,000 gamerscore.
Play One Box Co-op for 3 Hours
Play One Box Co-op for 1 hour
Win 10 Piñata shows
Win a Piñata show
Knock 1 Sweet into a Seed Hole from Long Distance
Grow all Arctic plants to maturity
Grow all Desert plants to maturity
Restore all of Piñata Central’s Computer Records
Wear a Piñata 'Costume'
Obtain a Choclodocus
Collect milk from a Flapyak
Make all Arctic species resident
Create 10 Wildcard Piñatas
Create a Wildcard Piñata
Win 10 Piñata races
Win a Piñata race
Have a Woo Woo Train in the garden
Have a Spectral Locomotive in the garden
Complete all Challenges in all Regions
Complete all Challenges in Region 7
Evolve a Polollybear from a Fizzlybear
Complete all Challenges in Region 3
Complete all Challenges in Region 4
Make all Desert species resident
Complete all Challenges in Region 6
Earn a Gold Combat Medal
Evolve a Parmadillo from a Fudgehog
Complete all Challenges in Region 2
Complete all Challenges in Region 5
Evolve a Chocstrich from a Cluckles
Evolve a Hoghurt from a Rashberry
Teach 10 Piñatas all of their Tricks
Teach a Piñata all of their Tricks
Make 3 Desert species resident
Evolve a Pieena from a Pretztail
Packet contains all surface types
Create 10 sets of Twin Piñatas
Make 3 Arctic species resident
Evolve a Moojoo from a Doenut
Restore 30 of Piñata Central’s Computer Records
Complete all of Langston’s Destination Challenges in Region 1
Create 1 set of Twin Piñatas
Restore 10 of Piñata Central’s Computer Records
Use 10 different Piñata Cards
Take a Special Photograph
Use a Piñata Card
Play 4 Player Online Co-op for 1 hour
Knock 5 Sweets into Seed Holes using the Shovel
Take 10 Photographs (Normal)
Obtain a special Piñata from the website (or trade one with someone who has)