Barrier which repairs itself.

[knasser2]

I have a tank that creates a semi-permanent force field before it as it advances. Can't really alter this as this is how it must work according to the fluff of the system I'm converting from.

 

I want attackers to be able to overload it temporarily through sheer firepower. This part is easy - it's the basic power. But I want it to be able to "come back up". The idea is you have to hit it hard and quickly and it's hard to keep it overloaded. I can't see a way of doing this in the rules. Should I just have it "re-cast" every Turn if it's not at less than half it's starting Body? Would that be a Trigger?

[dsatow]

If you are using barrier in 6th ed, then simply recreate the barrier.  It will be recreated at full BODY.  If you want a slower BODY recovery, you can always take healing, BODY only, usable every turn or regeneration usable on others, barrier only.

[unclevlad]

6E147-8.  Bottom para on 147, continuing to 148.  Discusses "Star Trek force fields" that get worn down.  That's part 1.  Part 2 might be an Aid, Always On, to the resistant defenses.  This is the shield generator.  I think you can throw in an Extra Time limit so the Aid only kicks in occasionally, but this might not be needed if the whole vehicle speed isn't very high.  So you can try to burn through the shields, but you haven't got long before they're back to full.

[Christopher R Taylor]

You can buy the power Regeneration to do other things than Body with GM permission, he might let you buy it for your barrier (be somewhat expensive in real points to get it fairly quick but the "barrier only" limitation has to be worth a fair amount of limitation).  Healing could do the same thing with GM permission again.

[knasser2]

Thanks! Three good answers, all different - it's the Hero way!

 

Just re-casting it after failure seems the simplest. It depends on whether I'd like it to be worn down over time and then come fully back up or if I want it to rebuild more slowly. I think I'd like it to come back up bit by bit so players get a nice feel of this constant pressure to keep it down rather than the more frustrating "we got it down and then suddenly its back, that was pointless". So for that reason alone, I'm going to go with one of the regeneration variants. And of the two, slapping on a Regeneration power is easiest. I'm not worried about cost particularly because I am the GM! Players might get their hands on this tank for a bit, but if they do, good for them!

 

So my tank now has the following:

 

Serpent Shield (Barrier, rPD 20, rED 20, 20 BODY, 5mx4m front of tank only (90CP); Non-Anchored +10CP; Mobile +¼; One-Way Transparant (Vehicle's Attacks Only) +½). 175AP / 175RP

Serpent Shield Generator (Regeneration, 4 BODY per Turn, 64CP; Serpent Shield Only -1). 64AP / 32RP.

 

I should possibly give the generator Linked, but I think not. Five turns to completely regenerate feels about right. It gives the PCs a window of opportunity once they've brought it down but still creates a feeling of urgency. It's supposed to be tough. Plus the shield is only to the front of the tank so there are tactical bypasses.

 

There's one final touch which would be nice but I think it might be more complex than it's worth. Fluff-wise this is a force-field and it flickers off for fractions of a second for the tank to fire. Basically it's synchronised to the tanks own weaponry. I know it will come up that players will want to try and time their shots to be at the same time as the tanks. Which would be very hard but juuuuust possible. I like the idea of a heroic PC judging it just right to get that critical shot through. Anyone have any idea how I could tweak this to make something like that possible?

 

EDIT: This is the Eldar Wave Serpent from WH40K that I'm creating rules for, if anyone is interested.

 

[Doc Democracy]

6 hours ago, knasser2 said:

There's one final touch which would be nice but I think it might be more complex than it's worth. Fluff-wise this is a force-field and it flickers off for fractions of a second for the tank to fire. Basically it's synchronised to the tanks own weaponry. I know it will come up that players will want to try and time their shots to be at the same time as the tanks. Which would be very hard but juuuuust possible. I like the idea of a heroic PC judging it just right to get that critical shot through. Anyone have any idea how I could tweak this to make something like that possible?

 

Essentially you have a custom limitation here that completely negates the barrier.  I would decide how likely it is, probably +0 limitation for how often it is likely to happen.  You then have to decide how they might go about this and put in a limitation of "not versus attacks where opponent makes a [something] roll".

[Ninja-Bear]

6 hours ago, Doc Democracy said:

 

Essentially you have a custom limitation here that completely negates the barrier.  I would decide how likely it is, probably +0 limitation for how often it is likely to happen.  You then have to decide how they might go about this and put in a limitation of "not versus attacks where opponent makes a [something] roll".

Doc I was figuring out how to do this for something else. Thanks.

[unclevlad]

Well, that force field flicker might be a small limitation, IF this is the main defense.  But the limitation may relate to the attack power:  Not when under a Continuous Attack.  Because you can't drop the FF.  As far as targeting it?  Notionally, the window's on the order of MAYBE 0.1 seconds, and most likely...a lot less than that.  Sci fi weapons usually mean you're including light speed energy beams and near light speed particle beams/bursts, so even a tenth of a second is a LONG time.  

 

I suppose in theory something like Find Weakness and Precog?  Find Weakness to even realize the opening is there, then Precog to give you a shot to know in advance...but even with something like this, the time window's just so brief.  Unless the source material suggests it's intended to be a (barely exploitable) weakness, it's just foo.  The "drop, fire, restore" sequence is just a way of saying the attack doesn't require BS explanation like "it phases through the field."  It's pure hand waving.

[Doc Democracy]

That is an interesting point unclevlad...

 

If you need to lower your shields to fire then is that a limitation on the shield or on the attack??

 

Cannot attack if under continuous attack, or shields do not work against continuous attacks in segments when weapons used.  I think the second looks more apt and the limitation would depend on how common continuous attacks were in the campaign.

 

 

Doc

[knasser2]

11 hours ago, unclevlad said:

Well, that force field flicker might be a small limitation, IF this is the main defense.  But the limitation may relate to the attack power:  Not when under a Continuous Attack.  Because you can't drop the FF.  As far as targeting it?  Notionally, the window's on the order of MAYBE 0.1 seconds, and most likely...a lot less than that.  Sci fi weapons usually mean you're including light speed energy beams and near light speed particle beams/bursts, so even a tenth of a second is a LONG time.  

 

I suppose in theory something like Find Weakness and Precog?  Find Weakness to even realize the opening is there, then Precog to give you a shot to know in advance...but even with something like this, the time window's just so brief.  Unless the source material suggests it's intended to be a (barely exploitable) weakness, it's just foo.  The "drop, fire, restore" sequence is just a way of saying the attack doesn't require BS explanation like "it phases through the field."  It's pure hand waving.

 

Well, we all know players are sneaky little gits. If there's a weakness they'll want to exploit it in-game and they'll arrive at it as simply as: "Wait - so it can fire at us but we can't fire at it? " / "Well the force field is synchronised to the shots it fires." / "Carol, run in front of it and get it to fire at you, I have an idea..." I like to be ready for such things so that I'm playing fair with them.

 

There are laser weapons in the game (also plasma), but this particular tank has a machine gun variant called a shuriken cannon. Basically a rapid fire electro-magnetic rail gun that streams out tiny monomolecular edged discs. I figure bursts are probably about a third of a second. It's not much but with great skill and perhaps one's own rapid fire weapons, they should have a chance.

 

Not able to fire whilst under fire is an interesting idea which would fit, but in this case I want to stay close to the original.

[unclevlad]

What IS the original?  You're inferring characteristics that may or may not be accurate.  Does this feature actually get exploited in the original material?  Does an enemy actually ever get attacks in while the shuriken cannon is firing?  

 

If the answer is No, then we have to believe the design intent is it is *not* exploitable, ergo the window is short.  A rail gun like that can be multi-barrel and the potential RoF is *insanely* high.  I'm hearing something like a capacitor-discharge kid of approach where you build and store a charge, then just *flush* the capacitor in next to no time to fire.

 

If the answer is yes, it is occasionally exploited, then that's saying the window is open for a decently long period of time.

 

Personally?  I don't buy it's open for long at all.  Or this thing would be toast.  Forget the PCs doing it;  ANY ENEMY would understand this one heckuva lot better from combat observations.  And with laser weapons and computerized weapons control, 1/3 of a second is an absolutely *fatal* window of vulnerability.  The enemy has the sensors, the sensors are linked into a fire control system, and the weapons have the kind of speed to exploit the characteristic.  Think of these things in the original context.

 

Doc:  your "shields don't work in segments when the weapons fire" just means everyone just holds, if necessary.  You're creating a window that lasts until the tank's next phase.  Now, ok...another way to do this is "In a specific segment where the weapon fires, the shields have an Activation Roll."  That represents a pretty narrow window where they're down.  I'd never make this harder than a 16-, personally.  Go back to the original post tho...that the way to take out this tank is to press attacks against it to deplete the shield generator, NOT wait for the potshot.  

 

Secondary aspect:  is the FF the tank's only defense?  Or does it have armor?  The FF might be taking it from Pretty Tough to Darn Near Untouchable as long as it's running.  OK, *now* you can impute the whole activation roll on the FF, only in the segment where the cannon fires, and call it a 14-.  The armor takes a bit of a pounding from time to time.  I'm still not sure that I'd ever let PCs improve on this, because again...enemy combat weapons systems have everything to exploit this, fundamentally built in.  So if it can be done, it would be done.

 

[eepjr24]

I don't know Eldar stories that well and there are a ton of them out there, but I have never heard of someone exploiting the timing of a wave serpents shots. If someone wanted to try it, I would probably impose a skill roll and OCV firing penalty. I assume there are countermeasures in place for this type of thing, like random cycle times, etc. So something along the lines of a System Operations roll at -6, maybe -4 if you have absolute time sense. And then OCV penalty of -12 or so, this is considerably harder than something like a head shot in my mind.

 

- E

[knasser2]

1 hour ago, unclevlad said:

What IS the original?  You're inferring characteristics that may or may not be accurate.  Does this feature actually get exploited in the original material?  Does an enemy actually ever get attacks in while the shuriken cannon is firing?  

 

If the answer is No, then we have to believe the design intent is it is *not* exploitable, ergo the window is short.  A rail gun like that can be multi-barrel and the potential RoF is *insanely* high.  I'm hearing something like a capacitor-discharge kid of approach where you build and store a charge, then just *flush* the capacitor in next to no time to fire.

 

If the answer is yes, it is occasionally exploited, then that's saying the window is open for a decently long period of time.

Personally?  I don't buy it's open for long at all.  Or this thing would be toast.  Forget the PCs doing it;  ANY ENEMY would understand this one heckuva lot better from combat observations.  And with laser weapons and computerized weapons control, 1/3 of a second is an absolutely *fatal* window of vulnerability.  The enemy has the sensors, the sensors are linked into a fire control system, and the weapons have the kind of speed to exploit the characteristic.  Think of these things in the original context.

 

Okay. This is for my WH40K conversion. The tank is an Eldar Wave Serpent. Eldar are essentially Space Elves. Only they make regular elves look positively humble by comparison. The Eldar word for humans is "Mon-Keigh". Their technology is highly advanced. The fluff and rules for Wave Serpents has varied with the years. The originals were pure troop transports and had no armaments. Later versions made them flying tanks and added projectile weapon armaments. The force field is not their only defence. They are also quite well armoured physically. Around the same level as a human fast tank, a hair under a human main battle tank. And far faster.

 

Human society in the setting is verging on post-Apocalyptic. They have advanced technology but don't understand it. There are whole automated factories that churn out tanks and nobody dares tough anything for fear of it stopping and them not being able to start it up again. Technology is worshipped and ritualised. A skilled tech-priest might figure out how to pull off what you're talking about (especially if they're a PC), but chances of it becoming a widespread feature of human weapons is effectively zilch. Humanity has essentially become a cargo cult. And ork technology is a complicated subject to say the least.

 

The fluff doesn't say it flickers. (Though it ripples, apparently!). However, I see the RPG version as an opportunity to fill in some of the fine points that the wargame doesn't. Players will certainly ask how it's possible to go through it one direction and not the other so it's either flickering or declare you can have one-way force fields in the setting. I dislike the mental image of the latter so flickering is how I'm explaining it.

[knasser2]

1 hour ago, unclevlad said:

Secondary aspect:  is the FF the tank's only defense?  Or does it have armor?  The FF might be taking it from Pretty Tough to Darn Near Untouchable as long as it's running.  OK, *now* you can impute the whole activation roll on the FF, only in the segment where the cannon fires, and call it a 14-.  The armor takes a bit of a pounding from time to time.  I'm still not sure that I'd ever let PCs improve on this, because again...enemy combat weapons systems have everything to exploit this, fundamentally built in.  So if it can be done, it would be done.

 

A bit more context. It's a troop transport / deployment vehicle and the shield is only at the front. So PCs have the possibility of getting round the sides and back with good tactics. The primary military intent of it is to charge forward into and possibly through enemy lines and disgorge a squad of soldiers (typically CQC specialists) in amongst them. It's a setting where people have actual chainsaw swords. It's pretty gonzo.

[knasser2]

5 minutes ago, eepjr24 said:

I don't know Eldar stories that well and there are a ton of them out there, but I have never heard of someone exploiting the timing of a wave serpents shots. If someone wanted to try it, I would probably impose a skill roll and OCV firing penalty. I assume there are countermeasures in place for this type of thing, like random cycle times, etc. So something along the lines of a System Operations roll at -6, maybe -4 if you have absolute time sense. And then OCV penalty of -12 or so, this is considerably harder than something like a head shot in my mind.

 

- E

 

OCV -12 is a bit strong at the power levels for this game. Though Space Marine characters might pull it off. And I want the shield to still be struck if they fail. I think I'll just keep the first part and have a pre-roll to get the timing. It'll ramp up the excitement for the coming Attack Roll if they succeed at it. I might modify it if they have Autofire as that would make sense.

 

I don't expect this to be a routine thing, but I'd like to let them try.

[eepjr24]

7 minutes ago, knasser2 said:

 

OCV -12 is a bit strong at the power levels for this game. Though Space Marine characters might pull it off. And I want the shield to still be struck if they fail. I think I'll just keep the first part and have a pre-roll to get the timing. It'll ramp up the excitement for the coming Attack Roll if they succeed at it. I might modify it if they have Autofire as that would make sense.

 

I don't expect this to be a routine thing, but I'd like to let them try.

Your game, your choices. ? Also remember they can set and brace, use teamwork skills, buy weapon specific CSL's, get targeting computers, laser sights (or other weapon enhancers), etc.

 

A skill roll penalty alone is going to be way easy to beat if they face Wave Serpents on a regular basis. If you go that route, I would make it an opposed skill test. The first time or two you can assume the pilot / gunner is unaware of what they are trying. Later they can be more aware and have higher skills as "only the fittest" survive combat. If it turns out to not be a problem then no sweat, just let them keep trying.

 

All this assumes that they have something that can dent a Wave Serpent once they get past the force field. In that case, then maybe just the threat of being able to get past the FF will change the enemy strategy and make them drop troops further back or just bomb them from orbit.

 

- E

Edited June 22, 2018 by eepjr24
Added notes on OCV.

[knasser2]

1 minute ago, eepjr24 said:

Your game, your choices. ?

 

A skill roll penalty alone is going to be way easy to beat if they face Wave Serpents on a regular basis. If you go that route, I would make it an opposed skill test. The first time or two you can assume the pilot / gunner is unaware of what they are trying. Later they can be more aware and have higher skills as "only the fittest" survive combat. If it turns out to not be a problem then no sweat, just let them keep trying.

 

All this assumes that they have something that can dent a Wave Serpent once they get past the force field. In that case, then maybe just the threat of being able to get past the FF will change the enemy strategy and make them drop troops further back or just bomb them from orbit.

 

- E

 

Ah, the Inquisition approach.

 

Opposed roll works for me. I like it and, as you say, it gives the pilot a way to respond which I like.

 

I don't think this will be a commonplace occurrence, don't worry! But when they do come up against one it'll probably be in some sort of siege scenario where there are convenient heavy weapons points for them to man. I run quite gritty, tense games. So every now and then I like my players to have a Christmas morning experience where they get to break out the big toys. Can't have a triumph without a challenge!

[unclevlad]

eepjr's got the sense of what I meant.  I know the WH universe...very loosely.  The point I was trying to make is, the source material almost never gets down and dirty.  You're inferring details like the cycle time based on your interpretations.  I and eepjr are pointing out...go to the source books and see how it's described *in action* there.

 

So the point that it's a fast assault troop carrier is important.  It's a #1 shield, in Star Fleet Battles terms...forward facing.  And only #1.  That's inherently massively limited already.  As you note...get onto the flank of the darn thing.  Light fast vehicles have armor for handling squad- and platoon-level weapons like machine guns and RPGs...but not serous guns like a helicopter autocannon.  (Speaking in present day terms.)  

 

If PCs can exploit the shield drop, it's a totally useless vehicle in real combat, IMO.  They already have ways to go after it.  

Here's one tactic that saw real world use.  IEDs and mines were *devastating* against Strykers.  The underside wasn't well armored.  Option 2, if it's not a hovertank, a sufficiently resilient barrier across the road.  Opton 3:  anti-tank missiles often attempt to strike coming straight down, into the top face of the vehicle.  This is often a weak point in the armor...especially for a troop assault vehicle.