Here is the full list of all 50 Plants vs. Zombies: Battle for Neighborville achievements worth 1,000 gamerscore.
Promote 20 characters to the rank of Master
Defeat Major Problem
Complete "Will You Be My Posse?" quest in Mount Steep
Complete "Treasure Hunt" quest in Mount Steep
Complete "The Genuine Article" quest in Mount Steep
Defeat Dreadwood
Collect 75 medals
Complete "Be Kind, Rewind!" quest in Weirding Woods
Complete "Zombie Prepared" quest in Weirding Woods
Play PvZ theme on piano (G# A G# A F D)
Complete "Becoming One With The Dumb" quest in Weirding Woods
Spawn 25 bots
Vanquish 100 zombies in PvP
Vanquish 100 plants in PvP
Revive 10 allies
Earn 200 vanquishes as an Imp
Earn 200 vanquishes as an Engineer
Give 1,000 overhealth as a Scientist
Earn 200 vanquishes as a Space Cadet
Earn 20 vanquishes using Crater Maker as a Space Station
Earn 200 Vanquishes as a Captain Deadbeard
Earn 200 vanquishes as an Electric Slide
Earn 20 vanquishes using Disco Tornado as an Electric Slide
Earn 200 vanquishes as an 80s Action Hero
Block 1,000 damage with a Dummy Shield as an All-Star
Earn 20 vanquishes using Rocket Ride as an 80s Action Hero
Earn 200 vanquishes as a Super Brainz
Earn 200 vanquishes as a Foot Soldier
Defeat Olds Cool
Earn 200 vanquishes as a Rose
Vanquish 35 gnomes
Earn 200 vanquishes as a Cactus
Earn 200 vanquishes as a Snapdragon
Block 1,000 damage with Peel Shield as a Citron
Earn 200 vanquishes as a Night Cap
Use Shadow Sneak for 1,000 feet as a Night Cap
Earn 200 vanquishes as a Chomper
Earn 200 vanquishes as a Kernel Corn
Earn 20 multi-vanquishes using Roll for Damage as an Oak
Spawn 25 pots
Use 25 expressions
Earn 200 vanquishes as an Acorn
Get a score of 25 or higher in the Dance Hall of Obedience
Vanquish 25 enemies while on a Giddy Park ride
Complete "I Treasure You" quest in Sundrop Hills
Complete "Fight Zentrificiation" quest in Sundrop Hills
Earn 200 vanquishes as a Peashooter
Dish out 1,000 overhealth as a Sunflower
Complete "Baron-Palooza" quest in Sundrop Hills
Destroy 20 targets at target range