Look Sharp Achievement
Destroy 10 teleportersTeleporters first appear during Wave 7. You will encounter 1-3 of them.
The easiest way to earn this is to play up to Wave 7, destroy however many teleporter enemies there are by any means then quit to the main menu without completing the wave. When you choose to start a game, you will have two options: ‘Continue Game’ or ‘New Game’. Select ‘Continue’ and you will resume at the beginning of the wave. Repeat this process until the achievement unlocks.
If you have the hammer and/or rockets equipped, you can work on Hammer (200G) and Exploder (200G) at the same time.