Here is the full list of all 29 Worms W.M.D achievements.
Complete all Challenges
Kill 500 worms
Get 40 kills using a Mounted Gun
Fully customise a team of worms
Gain a Gold Medal on all Training levels
Complete 5 Challenges
Complete 40 Sub Goals
Craft 30 weapons across all game modes
Complete 15 Campaign Missions
Kill 4 worms in a single turn
Win an online multiplayer match in Sudden Death
Collect a wanted poster
Complete all Training levels
Complete all the Basic Training levels
Complete Navigation Training
Finish a game with a worm on more health than it started with
Complete the Campaign
Craft every weapon in the game
Kill 20 worms with Prod
Reach Sheep Rank
Get 80 kills in a Tank
Get 80 kills in a Mech
Get 80 kills in a Helicopter
Play a Ranked Match
Play 50 Online Multiplayer Games
Win 3 online games in a row
Win an Online game with all worms in Buildings
Complete all the Sub Goals
Unlock all the Customisation Items