The MHC-10 is the military variant of the HC-8, featuring much stronger, 1000HP engines, a turret with a light cannon and a coaxial machinegun, some armor plating, underside torpedo socket with 5 torpedoes - enough to kill the USS Beast -, one more underwater rudder, somewhat larger wheels for going through rough terrain, countermeasures against AGM, and 2 (hell of a heavy) magnetic anchors even.

CONTROLS:

AG1 - Activate engine 1
AG2 - Activate engine 2
Throttle - Engine thrust
VTOL - Propeller pitch (for fastest speeds, keep it centered, but if you see it overspeeding, push it further away from it - upwards (but not fully to keep going forth, downwards (but not fully) to reverse.
Gear - Extend/Retract underwater rudder (extended by default, retract when going on land)
Yaw - Rudder yaw
Roll - Turret yaw
Pitch - Turret pitch
Trim - Winch for anchors
AG3 - Activate magnet for anchors