Here is the full list of all 14 Worms Clan Wars achievements.
Create your own clan, complete with emblem
Fully customise your worms
Complete all Worm Ops missions
Defeat the evil Lord Mesmer
Complete "Fugu Fountain"
Complete "The Class Act"
Kill a total of 100 enemy worms
Complete "Worm On Trap"
Complete "Meat In The Middle"
Kill a total of 10 enemy worms
Complete "The Mission Before Time"
Kill a total of 300 enemy worms
Win a ranked Clan Match
Complete a multiplayer match using your personally created landscape