Lasers fire beams that reaches instant across the arena and lasts between 0.5 and 1.0 second - having the effect that only a "full" beam contact delivers full damage. It fires every 2.5 seconds. Because of it's long reload, it causes more damage when fired. The damage shown on the info of your laser is per second, so a full laser blast will do 2.5 times the stated damage.
Laser is unlocked upon reaching Stage 5 prestige 0. It the first part you can unlock. The ultimate version of this is the Christmas laser.
If your opponent has a high ranged attack stat then the Laser can put you at a disadvantage. You may be destroyed before you ever get to fire. Use fast fire weapons instead, like rocket or minigun. To buy more time for your laser to fire, you can use backpedals or other gadgets (depending on the position of gadgets slots) to survive long enough to fire. Lasers are ideal for bodies with tons of health as they may live long enough to fire twice.
There is also a special tactic that uses a sneaky with no tires and specially placed gadgets to fly through the air flipping and shooting your enemy from midair. It will have to one shot the enemy, or else there will be a chance you won't be able to fire at the enemy again (depending on how you land).