First of all, this is (as the name say) a low part count, but it may not be totally mobile friendly, but I'm sure you can run it if you low some graphic settings ;). Oh, This is the description of The Original Build, so somethings might be different, but the controls are same (I think). I Also removed the Tracks mod, so the mobile players can use it. Have fun!

Betelgeuse A1

Meet the Betelgeuse A1-MBT, a fifth generation MBT and a milestone in the evolution of tanks and the war industry. Created by the association and cooperation of the largest war technology companies in Europe with the aim of creating a new tank from scratch that will change the scenario of wars taking place around the world.
A tank which can perform several tasks at once and occupy the function of dozens of vehicles alone, capable of killing infantry, air targets, ground targets, sea targets, enemy bases, transporting soldiers, short and long distance attacks between others.
Its monstrous arsenal is enough to scare any enemy, a 175mm autoloader cannon, a 35mm automatic cannon on top of the main turret and another 20mm coaxial, 7 surface-to-air and 7 surface-to-surface missiles. Moreover, its armor and mobility are equally excellent, being faster than and not suffering major damage by most MBTs today.
Obviously, to hold all these things, a very large hull is required, which may be the only negative point of this tank, a great big target, but its Active Protection System (APS) guarantees almost invulnerability against several attacks. If it is not enough, its armor can take care of the rest, it can also be equipped with Reactive Explosive Armor (ERA) for more protection.
Here are the commands, pay attention to each one; it can be difficult to control the tank right at the beginning, but quickly you get it.

Commands:

•Already On: The main armament (175mm), the 20mm coaxial Cannon, Turret and Tank movement are Already on.
•AG1: Lock the turret movement and allows using the commander camera positioned on the top of the vehicle with VTOL and Throttle (Use it to Lock the missiles on the Air or Ground Targets)
•AG2: Allows the secondary (35mm) to move itself and lift up the Radar, It will automatic aim on ground and air targets as soon as you select one of those.
•AG3: Allows the use of the missiles. Lock in the targets using the commander camera.
•AG5: Turn on the lights.
•AG7: Light up the Main armament Aim camera for night mode.
•V: Launches the Flares and Smoke (This is also a substitute for the APS).
•Roll: Control the movement of the tank (Left and Right) With AD.
•Pitch: Control the movement of the tank (Forward and Backward) With WS.
•Yaw: Controls the movements of Turret (Horizontal Axis) (Left and Right) With QE.
•Trim: Controls the elevation of main armament (with Up Arrow and Down Arrow. The left Arrow reset the trim to neutral (0º).
•Throttle: Controls the elevation of the commander sight.
•VTOL: Controls the horizontal axis movement of the commander sight.
•Brake: Brakes.

-Guide of Cameras:

•Cam 1: Secondary armament gunner sight. Use it to see where the 35mm is aiming and see your surroundings.
•Cam 2: Main Armament aim camera. Use it to aim the 175mm.
•Cam 3: Driver’s hatch sight. Use it to feel like you are driving.
•Cockpit: It’s the commander sight. Use it to aim and Lock the missiles.

The Main Armament:

A big tank needs a big cannon, and this is a massive one, the Rigel 175mm cannon, capable of firing projectiles at 1150m/s, which gives it a great range. It have an autoloader that gives you 4 seconds of reload time, with 40 projectiles ready to be fired. With a cannon like that, it is easy to destroy any target, but maybe it will be hard to aim in the first time. Use Trim to control the elevation, QE to control the horizontal axis, select Air-to-Ground and use Alt to Fire. The two-plane stabilizer will maintain your cannon stability and target in range of firing, but at fast speed or hard turns it won’t work well (The two-plane stabilizer I tried to do did not work very well, but it can maintain the target at the cannon aim camera sight).

The Secondary Armament:

The Aldebaran 35mm Automatic Cannon have an auto-aim feature (used the formula of !@SenSkysh that you can see there (https://www.simpleplanes.com/a/SN9nKo/AUTO-AIMED-TURRET-AK-2100), so you just turn the Guns to Air-to-Air or Air-to-Ground and the turret will aim at any target in the cockpit range. If it do not select one, you can do it yourself just by clicking on it, after that, press Alt (by default) to shoot. (If select Air-Ground you will have to select the weapon that will shoot; 175mm by default). However, because of the cockpit is placed a little to the right, the aim might not be very accurate, but it is deadly at 1,5 miles or least for planes and 5 or least to ground vehicles. The Alnitak 20mm Automatic Cannon can take down weak armored vehicles and infantry. (BUG alert: Because of the fast firing rate, the sound and the flash of the Aldebaran 35mm can bug sometimes).

The Missiles:

The Bellatrix Missile Launcher System (BMLS) of this tank have 7 missiles of each type (Ground-Air / Ground-Ground), 14 in total. They are located on the top right of the turret and can be activated by AG-3, use the commander sight (AG-1) to lock on targets, they are all fire and forget so you can fire at multiple targets. (Check if the 35mm cannon isn't above the missiles bay before firing).

The Commander Sight:

With so many moving parts, I had to improvise a bit, so the controls of the Commander Sight may be tricky at first, but you can adapted to it fast. After activating AG-1, use Throttle (Shift and Ctrl by default) to move the vertical axis and VTOL (X and Z by Default) to move in the horizontal axis. Use it to lock at the targets for the missiles or if you want to have a more realistic gameplay use only it to see your surrounds.

The Armor:

The Betelgeuse A1 have an excellent armor on every part, especially on the front, the only weak spots are the observers, the radar, the secondary armament and the flares dispensers and the exhauster, but lose them will not destroy your tank (Probably). The three main crewmembers are enclosure on a shielded capsule on the front part of hull, and another one on the back capsule; all the functions are controlled remotely.

Tracks:

Yes, I decided to use the mod, I hope it doesn't cause much problems for you guys, but it make much easier to build, it also make more realistic, I’d recommend.

Lights:

After you activate AG-5 only a part of them will be on, this is a feature, if you brake the other red lights will turn on, and the yellow ones turn on when you turn the hull to the left or right.

A little about the inside:

A little about the outside:

Blueprint:

Specifications:

• Weight: ~138,000 lbs. (62,5 tons)
• Length: Gun forward: 52,1 ft. (15,88 m) / Hull Length: 38,5 ft. (11,73 m)
• Width: 20,7 ft. (6,31m)
• Height: With antenna: 16,9 ft. (5,15 m) / Hull Height: 10,5 ft. (3,2 m)
• Type: MBT (Main Battle Tank)
• Crew: 4 (Driver, 2x Gunners, Commander) (More 4 infantry)
• Armor: Composite armor (360-1200 mm)
• Main armaments: 1x 175mm Rigel Cannon (40 rounds) – Angles: vertical: 20º/-7º; horizontal: full turn at 30º/s. Reload time (with autoloader): 4 sec.
1x Bellatrix Missile Launcher System (BMLS) (7x Surface-to-Air missiles (SAM) / 7x Surface-to-Surface missiles (SSM))
• Secondary armaments: 1x 35mm Aldebaran Automatic Cannon (2000 rounds) (Automatic Aim) – Angles: 90º/-10º; Full turn.
1x 20mm Alnitak Automatic cannon (4000 rounds) (Coaxial).
• Engine: Saiph1400 (Multi-fuel) 1400hp
• Fuel Capacity: 639 gallons (2.419 L)
• Operational Range: 640 km (on road)
• Max/min Speed: 55 mph (88 km/h) / 25 mph (40 km/h) (on plain road)
• Manufacturer: Zharapparbyell Ind.
• Origin: European Union
• Unit Cost: 12.8 million US dollars
• Production Period: 2041-Present
• Quantity produced: 1 operating unit

Bug Alert

The Main Armament (175mm) is firing ghost shells, to fix this bug do like this: Put the In-game mod Overload > Selct the Main Armament > Set DisableAircraftCollisions to False (It should be True whe you open it). Like that:

ORIGINAL VERSION HERE

If you want to use any part of this tank for some of your projects talk to me before, just to know. Thanks for the support of all, comment what you have found of this project and also upvote, enjoy and see my other projects, I think you'll like, Ideas to improve my projects are always welcome, if you really like this project, upvote it, do not forget.
Sorry for my English.

Credits:
Automatic Aim: @SenSkysh