Unlock the following medals in the "Medal Cabinet" under the options screen by performing the corresponding tasks:
MEDAL - HOW TO UNLOCK
100% Complete - Get a 100% game completion.
Annihilation - Win with a lot of health.
Beserker - Kill eight or more worms in one round.
Big Spender - Buy every item in the shop.
Boffin - Beat all puzzles, including the bonus levels.
Field Marshall - Win over twenty online games.
Laboratory - Beat all laboratory levels, including the bonus levels.
Outstanding Bravery - Make a comeback by winning when you are losing by a lot.
Rookie - Beat all training levels.
Tough Nut - Beat all campaign levels, including the bonus levels.
Veteran - Play twenty online games
Winning Streak - Win five games in a row.