Ontos Heavy Tank
Production information
Manufacturer Grumman Amalgamated
Kallon Industries
Production Year 2832[1]
Mission Close Combat
Type Tracked
Cost 2,267,363 C-bills
Technical specifications
Mass 95
Armor SimplePlate Manufacturers
Engine 285 HeavyLoad with PowerBoost ICE
Speed 54 km/h
Crew 7
Communications System Easy Talk
Targeting Tracking System GuideRite w/Laser Coordination Link
Heat Sinks 24
  • 8 x Medium Lasers
  • 2 x LRM-5s
BV (1.0)  ???
BV (2.0) 938


The vehicle that would eventually be called the Ontos started out as the first of three prototypes created by Grumman Amalgamated designers. While all three performed adequately, the Ontos was chosen due to to the fact that its main armament never needed to be reloaded in a protracted engagement. It is rumored that the designer for the Ontos was inspired by an ancient and obscure Terran vehicle that shared the same name.

The Ontos has proven popular throughout the Inner Sphere, especially so in the Free Worlds League where it is a mainstay in House Marik heavy tank units. It is often used as an ambush unit due to its short range and slow speed.

Earlier versions of the Ontos had problems with overheating that could burn out the power amplifiers. This issue was later corrected by forcing the lasers to fire in sequence rather than all at once.

Weapons and Equipment[edit]

The Ontos is armed with an array of eight Martell Model 5 Medium Lasers. This requires the Ontos to carry over 24 tons of power amplifiers and heat sinks, however the primarily energy weapon based armament means it can continue to fight on when supplies run short. Two Longfire LRM-5 missile racks provide covering fire for use when the Ontos is required to assault or move to a new position.


  • LRM 
    This 2876 variant of the Ontos removes the Medium Lasers and their supporting equipment for a more efficient pair of LRM-20 missile racks. The existing LRM-5s are upgraded to LRM-10 racks.BV (1.0) = ??, BV (2.0) = 1,249
  • Fusion 
    This 2863 variant takes a standard Ontos and installs a rare fusion engine. The armaments of this model are ten medium lasers and two LRM-10s with two tons of ammunition. Armor has also been added. BV (2.0) = 1287[2]
  • 3053 Upgrade 
    The influx of rediscovered technology allowed Grumman to replace the ICE with a new GM 285 Cold-Start Fusion engine, which removed the need for power amplifiers and increased available space. While four of the original medium lasers were retained, now Hellion V models, the remainder were replaced with a trio of Intek Medium Pulse Lasers. The twin LRM-5 racks were replaced by a single Delta Dart LRM-15 which utilized an Artemis IV tracking system. An additional Hovertec SRM-4 and Harpoon-6 SRM-6 missile rack, both mounting Artemis IV, were also added to further increase the Ontos' short range firepower. Protection was not ignored, with the new Ontos incorporating a CASE system, and mounting over nine tons of Ferro-Fibrous armor. BV (1.0) = ??, BV (2.0) = 1,242
  • Light Gauss 
    A further update of the 3058 Ontos, the Light Gauss Ontos removes all weapons to mount three Light Gauss Rifles, four tons of ammunition, and two ER Medium Lasers. BV (1.0) = ??, BV (2.0) = 1,269
  • MML 
    As an modification of the Light Gauss variant one of these weapons is replaced with 2 MML 7 launchers and the ammunition is protected by CASE. [3] BV (2.0) = 1,268[4]
  • HEAT 
    Produced by Quickscell Company. The Ontos HEAT (Hostile Environment Assault Tank) uses a Combat Vehicle Escape Pod to protect the crew in the event of a catastrophic failure. To provide protection from hostile environments, the entire Ontos is enclosed with Environmental Sealing. Equipped with an ER Large Laser and Enhanced LRM-15 for long range fire, it also mounts three Medium Lasers to fight at close range. Ten tons of Ferro-Fibrous armor protects against weapon fire. BV (2.0) = 1,173[6]

Custom Variants[edit]

  • Ontos X All-Aspect Assault Tank 
    Equipped with several experimental systems the Ontos X AAAT was undergoing testing for the LAAF on the world of Despair when it was seized by Captain Theobald West and his crew. Sealed against vacuum conditions and equipped with a Combat Vehicle Escape Pod, West and his crew used the NLRM-10 and eight Medium Lasers of the Ontos X to destroy all the vacuum-capable vehicles held by the garrison. They then ransomed several high ranking scientists back to the LAAF and disappeared. BV (2.0) = 962[7]

Design Quirks[edit]

The Ontos Heat variant is subject of the following Design Quirks:[6]



  1. MUL online date for the Ontos
  2. Record Sheets: 3039 Unabridged, p. 151
  3. Technical Readout: 3085, p. 191
  4. Record Sheets: 3085 Unabridged — Old is the New New, p. 53
  5. Record Sheets: 3085 Unabridged — Old is the New New, p. 54
  6. 6.0 6.1 Technical Readout: Prototypes, p. 63
  7. Experimental Technical Readout: Pirates, p. 11