Behold: The new Model IV mk.1 "Champion" MBT

Made up history:
In the 1980s Seitwälder had fallen behind somewhat in the cold war arms race. The old M3 chassis, even with ERA and other upgrades, could simply no longer compete with rival technology. The Typhoon tank was too lightly armed to fight modern enemies effectively as well. Thus, the Peregrine Armorconcept firm was tasked with creating a new tank capable of high maneuverability on and off road with the new and extremely potent 120mm K7A1 cannon. It was designated the XM4. The design was good and achieved what the Seitwäldan military needed, but in doing so its armor was weak enough to be penetrated by many types of enemy rounds. Unwilling to settle for this, Peregrine increased engine power and added armor, bringing it to an armor profile similar to that of the Leopard 2 series. The tank was re-designated XM4E1. At this point, research into ERA yielded wonderful results, so Peregrine covered the tank in ERA bricks, further improving survivability. Finally, the tank was ready for service. It was designated M4 and named the Champion.

Armament:
1x 120mm Smoothbore K7A1 cannon
1x 20mm external autocannon

Ammunition:
15x Mk. IV High-explosive-anti-tank-fin-stabilized shot (HEATFS) (Rockets)
10x Mk. VII Armor-piercing-fin-stabilized-discarding-sabot shot (APFSDS) (Rockets)
5x Mk.V High-explosive-squash-head shot (HESH) (Rockets)
10x Mk. III Wire guided anti-tank-guided-missile (ATGM) (Infernos)

Controls:
Countermeasures for smoke grenades (spam the button)
Pitch axis for gas pedal / reverse
Roll for turning
VTOL to turn turret
Trim to elevate / depress gun & autocannon
Yaw to turn external autocannon
Don't press a.g. 7 and brake. It's a totally bad idea (unless you like not having fuel).

Enjoy!