Thud gunner

The thud gunner is a tower weilding 2 machine guns that can aim and fire independently thus hitting 2 things at a time potentially (or both firing at one) its not perticularly high damaging but its rate of fire makes up for it, also its able to hit air but only does 80% of the damage

Base stats
Cost: 750 Credits    Damage: 25     Health: 1000       Rate of fire: high     Range: 10

it looks like a turret with 2 machineguns on the sides attached to ball bearings allowing free movement

Level 2
Cost: 1250 Credits    Damage: 25     Health: 1250      Rate of fire: high/Very high    Range: 11

it gains 3 orange stripes coming from the top going down and spreading out and gains the look of plate steel, and on each side it has 2 machineguns instead of 1 per side thus DOUBLING damage output not to mention the increased fire rate

Level 3
Cost: 2500 Credits    Damage: 75    Health: 1500    Rate of fire: Very high       Range: 13

The orange stripes become red and glow, it loses the ballbearings all together, sacrificing the extra 2 turrets and independant firing for 2 High caliber machineguns in the center, dealing vastly increased damage per shot and increasing fire rate, the rest of the turret (the area without red stripes) turn black with a carbon fibre texture

Maxed out upgrade
Cost: 3500 Credits    Damage: 125     Health: 1750     Rate of fire: VERY HIGH      Range: 15

The tower becomes larger in general, the red stripes get a thinner, brighter aqua stripe going down the middle, and the bullets are improved further, giving them red tracers, and giving them the potential to deliver collateral damage hitting the enemy behind them