Full list of all 12 A Kingdom for Keflings achievements worth 200 gamerscore. It takes around 8-10 hours to unlock all of the achievements on Xbox 360.
Finished a complete castle with three connected parts (Single Player)
Encountered every possible Kefling hat (Single Player)
Built a glorious statue of oneself (Single Player)
Collected 10 unique player banners from other giants during Xbox LIVE play
Build a cathedral (Single Player)
Reached a total Kefling population of 30 (Single Player)
Unlocked 25 blueprints (Single Player)
Played in an online game where 20 different player banners appear
Became the big bully of the village (Single Player)
Built a building made of more than 8 pieces (Single Player)
Built a lumbermill (Single Player)
Trained a Kefling (Single Player)