RoboBlitz

One of the harder achievements. Obviously set the difficulty to "Master Technician" when you're starting a new game and do not buy any upgrades as this will prevent you from getting the achievement (in case you thought you might be able to buy but not use them.)

Luckily you are allowed to use the upgrades you recieve from Karl and your starting weapon. This means you get to use the EMP rifle, the tractor beam, and the point to point beam. Since upgradium won't help you get through the levels you might as well try to rush through every level using the EMP's stun effect to prevent enemies from attacking you as you pass and the point to point beams ability to attach enemies to nearby scenery to slow them down and prevent them from chasing them and attacking you.

Of course you could always just go very slowly through the levels and try to use the EMP gun to kill everyone in your way but it seems to be much more difficult due to the weakness of the EMP gun.