So, I was wondering, in a galaxy rife with evil, and plied by starships that can destroy continents with their armaments, it stands to reason that some planets would have facilities erected to defend against enemy space craft. I have seen a TT write up for one, called the Duty's Fist, in my Apocalypse book. So, it is basically a Planetary Defense Cannon; my quandary to others is what sort of weapon, preferably from the books, would it be? It needs to be a big gun, preferably one with a hell of a kick, since it has to do some serious damage in a single hit, AND contend with Void Shields. Now, I'm not really looking for a one-hit kill cannon (though it would be nice), but I need a gun that can be a threat, and that means doing enough damage to matter, knowing that the next shot will be a counterattack from low orbit, where the facility will be destroyed, possibly.

As a second, how many ship components could work on a planet? If I had a plasma reactor, like that found on a ship, could the facility have torpedo silos, the big gun, and maybe a void shield of its own? I know the silos are in old Battlefleet Gothic, and I'm sure Titans mount void shields, so I don't see why a structure couldn't. A fortress, of sorts, with a PDC, missile silos, AA gun emplacements, and maybe a small, standing forc of PDF/IG, hiding behind a void shield, could be a nice opposition for a RT group, or a spendy investment they could make to protect a planet they have claimed, knowing they can't stay there and guard it. Opinions?

I am no expert, but I recall from the various bits of fluff I have read back in day (I played a lot of 40K in the 90s, but not in over a decade now), was that enormous great fortresses were not that uncommon, and major cities would have some sort of defence structure to deter space-borne attackers.

Probably the easiest way to design it for a game of RT would be choose a ship hull for approximate power comparisons (so a 'raider' defence system would be much smaller and weaker, but more commonly seen than a 'cruiser' defence system), and basically build a ship using the appropriate engine and weapon components (but with some/all weapon slots shooting 'up', as it were - a 'cruiser' defence system would have potentially 6 guns to bring to bear for instance). At its simplest, just treat them as space ships but without a warp drive. You should probably add about 1/3 to the amount of power generated by the engines though, as, clearly, none of the power is used for propulsion.

I suppose they should be better protected (allowing up to 3 shields should be allowed), and have use the 'internal bulkhead' and 'extra void armour' upgrades extensively. I suppose a lot depends on how much effort/time you want to do, but if I wanted to quickly build a defence station, I would just build what would, from a mechanics point of view, just be an immobile warship.

I suppose also you could borrow those enormous land ship things from Zayth descriped in Lure of Expanse, and make them immobile.

Well, they are easy solutions which spring to mind anyway.

Best of luck designing something,

All best,

David.

David B said:

But what gun hits hard enough, to emulate the big cannon? Ships have the advantage of mobility, but the base is a sessile target. It would need to hit hard enough to ward off an enemy, so that they don't just hide behind their void shields, and pelt the crap out of it, making for a spendy, but effectively useless defense measure.

Lances batteries, and heavy caliber AA defenses that can represented by Broadsides. Don't forget to give them good detection to spot the ships and acquire the targets.
On very wealthy and important planets, such as Scintilla or the Lathes, we can even suggest Nova Canons as a defense weapon.

By fluff, ground batteries (as opposed to orbital defences) tend towards laser weapons and torpedo/missile silos (presumably because building a "standard" gun that can fire out of the gravity well and still do significant damage is difficult).

Lances are certainly known to be used in such a capacity (and, indeed, given the hardly insignificant extra mass of an entire planet upon which to dump heat, can be more effective, as they can actually fire for longer)- possibly go with the Dragonfire Lance from Lure of the Expanse?

Torpedoes, as I mentioned, are also classic defences, with the bonus of having the opportunity of much larger opportunity for ammunition stowage.

For those occasions where they resort to "smaller" anti-ship missiles, a ground installation of Jovian Missile Batteries, possibly loaded with Atomics would seem to be the order of the day.

All of them should probably have the Turbo upgrade.

If one wanted to go with the "ultimate", then a ground-based variant of either Bombardment Cannons or possibly even a Nova Cannon may be possibilities.

Just from BFG's book itself lessee… There were ground based lances with a modified range of 12 and a strength of 3, probably a void sunder array with extended range and likely your Duty's fist. The basic version wasn't covered by shields but had a RT modified 24 armor. Shields would be quite possible for these as from the recent fluff books most large defenses did rate at least a single void shield.

Remember in gothic lances were the best way to take these things out and shipboard lances, not designed to fire in atmosphere had an only 50% chance even firing, while ground based lances were of insignificant cost(you could buy 11 for the cost of a cruiser) and could always fire in their chosen environment.

Besides that there were plenty of missile silos(you could buy 33 silos with a str 6 spread for the cost of a cruiser) which while also not shielded came en masse enough to really wreck someones day. Note that these silos while they possessed 24 armor as well, gained it in either being heavily shielded in mountains or hard as hell to hit as mobile truck or train mounted launcher arrays.

Don't forget air bases either. They still took only one hit with 6+ armor but you could buy 9 for the cost of a cruiser and they had the launch capacity of a Dictator, not a bad buy. They also had 2 turrets unlike any other ground defense.

By the looks of the book settings for orbital defenses on the average world, it looks like a quantity over quality aproach. Your duty's fist probably couldn't take a darn big hit, you're right there, but a planet could easilly support a dozen of them.

Regarding defences, I would suggest stacking up on void shields - going back to when I played 40K in the 90s, I remember a few little stories in Codices and White Dwarf on cities with impressively strong shields which needed ages to be worn down/over-loaded. For big defensive stations 4 (or even more) shields would be reasonable. In terms of sheer armour, a defensive station would be much more heavily armoured than just about any ship - I am no naval historian, but generally I recall that ships pretty much always lost in shooting matches with forts, to a large extent because damaging a fort is so much harder.

Regarding guns, well, if one gave it a cruiser level of armament (i.e. 6 guns, including 4 broad sides), but which could all shoot in the same direction, I reckon that would tear a huge hole in anything. One could justify the scariest weapons available, and one can always play with weapon craftsmanship to make the guns even more deadly. The idea of having air bases around it would also make the whole structure more potent.

One could also justify in some circumstances particularly good gunners in the fort. Attacking something with BS 50 is a lot, lot scarier than something with BS 30. One could also apply this to the skill of the technicians on the ground - who may be able to repair things very quickly indeed - it would make things even scarier for you players if they knew that if they suffered damage in a fight they could not easily remedy it, whilst the fort, supported by massive infrastucture and in friendly territory (and with perhaps a vast amount of quasi-slave labour to hand) could be repaired very quickly indeed.

I for one would be curious to see the final profile you come up with when you have finished,

All best,

David.