The Lucky Shot skillshot is achieved by killing an enemy with a cannonball from the Bouncer that travelled over one hundred meters without hitting anything. This is one of the hardest skillshots to earn, because it is difficult to keep enemies at the right distance and maintain a clear view of them. The cannonball must also be detonated on contact with the enemy or the ground, otherwise the skillshot will not be earned. Aim high into the air and if you do not hit your target, use it as reference when aiming your next shot.
It is also important to NOT hold the fire button indefinitely when attempting this skillshot; as doing so will cause the cannonball to bounce and make this skillshot impossible.