The Breakdown Add-on for State of Decay: Year-One has 16 achievements worth 250 gamerscore.
Reach Breakdown Level 2.
Go out in a Blaze of Glory at Breakdown Level 1 or Higher.
Destroy 5 Bloaters (Breakdown Level 2 or Higher).
Perform 50 Zombie Executions at Breakdown Level 3 or Higher.
Collect 150 Resources at Breakdown Level 4 or Higher.
Destroy 5 Juggernauts at Breakdown Level 5 or Higher.
Execute 50 Stealth Kills at Breakdown Level 5 or Higher.
Reach Breakdown Level 6.
Unlock All Heroes.
Reach Breakdown Level 3.
Reach Breakdown Level 4.
Reach Breakdown Level 5.
Complete All Research Projects (Breakdown Level 1 or Higher).
Burn 100 Zombies with Fire (Breakdown Level 2 or Higher).
Destroy 5 Ferals (Breakdown Level 3 or Higher).
Earn 25 Headshot Streaks (Breakdown Level 4 or Higher).