Here is the full list of all 28 Catan: Creator's Edition achievements.
Possess at least 3 harbors.
Build a road with 15 or more segments.
Collect 20 resources in your hand.
Rob your opponents 10 times in a single game.
Place the Robber on a hex where he will affect no one.
Win a game where you always had more Knights than City Improvements.
End the game having never lost a City to the Barbarians while never building a Knight.
Interrupt the longest road belonging to an opponent.
Win a game with more than a 5-point advantage.
Move the Robber to a player who currently holds no cards in his hand.
Find 5 treasures in a single game.
Win a game by having the Largest Army and the Longest Road.
Win a game without trading (fellow players AND bank).
Win a game without building a city.
Build settlements on all the islands in a Seafarers scenario.
Reveal 10 fog-covered hexes in a single game.
Play 12 Knight Cards in a single game.
Build your roads, settlements, and cities exclusively on coasts.
Build all your settlements and cities next to a single type of resource and win.
Only trade with your fellow players at least 2:1 in your favor and win.
Become "Defender of Catan" five times in a single game.
Get all 3 Metropolises in a game.
Have three Cities with City Walls in a game.
Cause 5 Barbarian attacks in a game.
Play and defeat all the computer characters in custom games.
Build a Settlement or a City at every number in a game.
Trade 42 times 1 Lumber for 1 Wool in a game.
Build a Mighty Knight, a City Wall, and a Metropolis and move the Merchant in a game.