The Legends of the Lawn Add-on for Plants vs. Zombies Garden Warfare (Xbox 360) has 10 achievements worth 250 gamerscore.
Grow a Laser Bean
Summon a Backup Dancer, Vampire Zombie and Heal Zombie
Vanquish Baron von Bats in Garden Ops
Vanquish a Treasure Yeti in Garden Ops
Collect 7 Diamonds from the Treasure Yeti
Defeat a Vampire Super Wave
Vanquish 50 Vampire Zombies
Capture 20 Gardens in Suburbination
Collect 50 Crazy Orbs in Vanquish Confirmed
Vanquish a Zombie carrying a Nacho Taco in Taco Bandits