Tri-gun

Tri-Gun is a tier 2 copter available at level 10. They have 3 guns and go well with fire rate, bullet damage and movement speed. Make sure you upgrade bullet damage to the max to maximize bullet damage

Strategy
The Tri-gun can be very effective with fire rate and bullet damage upgrades. As well of its bullet spread, keep the Tri-gun in close range, so all the bullets hit and to kill them almost no time, but even more effective with the Penta-Gun.