Renegade Legion Gravtanks

[namar13766]

Since Renegade Legion was also originally made by FASA, I was wondering if anyone ever made homebrew construction rules for Grav-Tanks in Battletech?

[Grand_dm]

I have often wondered the same thing about the hovertanks and powerguns of Hammer's Slammers.

[Starfury]

Long, long ago I did conversion rules for Renegade Legion into BT. A friend of mine also did Hammer's Slammers as well. The biggest issue was the line if sight range for powerguns, since the sensor systems on Slammer style vehicles can hit targets in orbit.  Your average Mech isn't anything in comparison.

[DevianID]

I feel like, in battletech rules anyway, the exotic grav tanks should be easy to stat up.  We already have rules for WIGE/vtols, so if you remove the massive motive hit table or rotor from them, as the grav system in Legion doesnt suffer motive damage, you basically have the movement type.  You just use WIGE if it cant go above level 1, starwars hovercar style, or vtol if it can fly as high as it wants.  Failing that, you would use aerospace fighter rules with velocity for the really fast grav tank stuff that flies several hundreds of miles per hour.

The 150-200 ton actual hoverskirt hovertanks in hammers slammers are kinda silly.  Its the small size/high weight thats the issue, they are smaller (dimensions) then a 10 ton real world hovercraft in terms of length/width, while still using traditional lift fans/skirts to generate ground effect.  The real LCAC, for example, is 185 tons and 26x14 meters.  But the 'Slammer' tanks are a similar weight, and still use a skirt, but are the size of a normal tank.  Also, the energy weapon is both high powered particle type but doesn't attenuate quickly in atmosphere/cause all the cancers, so its hard to say what its damage should be.  A battletech version of the standard hovercraft with a PPC main gun and 30-50 tons in weight does pretty much all the Hammers Slammers do, without the 180 ton bloated weight.  Unless someone can find a better description of why that massive weight in 'hammers slammers' matters, a 30 ton 2 crew or 45 ton 3 crew btech hovertank covers the capabilities as far as I can see.

[paladin2019]

A powergun is a plasma weapon, using a copper-cobalt alloy as the mass to be electrically plasma-cized. It is also ineffective if LOS goes through light woods (at least for the infantry-scale weapons.)

There is a lot of consolidated tech discussion in Pireme Press's Hammer's Slammers game.

[paladin2019]

The fundamental questions of directly converting RL grav-tanks are the raw speed (even before compounding for velocity) of the similar MPs scaled for 100m hexes and the associated ranges of weapons.

[worktroll]

It's an old hack, but a couple of decades ago we used the Hydrofoil construction factors (which allowed over 100 ton designs IIRC), and made them move like VTOLs.

The result is underpowered compared to canonical RL vehicles, but was a nice surprise to the players :)

[Starfury]

The fundamental questions of directly converting RL grav-tanks are the raw speed (even before compounding for velocity) of the similar MPs scaled for 100m hexes and the associated ranges of weapons.

And flicker shields.  I took the rate of a flicket shield and divided it by 10 to provide a TN penalty for incoming fire.  Renegade Legion Tanks also can carry engineering attachments which project lasers to clear out forests, digging cannons to create entrenchments, and also don't track ammo except for missiles, and  their artillery is capable of firing gravitcally induced nuclear explosions. 

[Failure16]

A large part of the mass from the Slammers' blowers stems from their need to use iridium for armor.

The sensor suites, fire-control, tracking, and communications systems are considerably more advanced than what is available to the BTU.

They do not use blown-air skirts, for the record, but rigid-steel aprons and they are technically classified as ground-effect vehicles as opposed to pure hovercraft.

The combat cars are tank-sized, but the M2 tanks themselves are easily 2-3 times the size of a modern MBT. I shall not debate ground pressure and other minutia, but they are not the size of a tank as we viscerally understand the term.

The present game, indeed published by Pireme Publishing, is called The Crucible.


The key to converting Renegade Legion gravtanks to the BTU--or vice versa--is fundamentally figuring out how weapons affect armor. The Rosetta Stone is nuclear weapons, since that is the primary real-world commonality between the two milieus.

Movement is easy. They move like VTOLs but with the aerospace mechanic of turn radii-based-on-velocity. They have better handling abilities; they do not sideslip and can reach incredible velocities that must be handled with care by the crew. They can enter all the same terrain a BattleMech can, including submerging in water, and can reach aircraft-level altitudes (but not orbits, by themselves, on a normal planet).

Once the damage-mechanic is settled, everything else will fall into place. The aforementioned special equipment, like planar lasers for cutting paths through forests, special munitions, etc., as well as infantry and fire support, do not need much conversion at all (though their infantry is considerably deadlier than the BTU's jump-infantry.