Worms Rumble

You'll earn coins as you play - in my first game I earned 1,150 coins.
Reach level 2 by gaining XP for killing enemies. This will unlock new customisation items that can be bought using the coins you've earned under the 'Worm' customisation tab on the menu.
The cheapest item available to me at level 2 cost 500 coins, and the first things that unlocked to be purchasable were under the Style/Headwear section. On purchasing anything here using coins this achievement will unlock.