You are a devil general in Avernus...

[HoboKnight]

...and were tasked to stop/push back/destroy endless demon hordes, constantly invading your hells. You are given vast armies that can fight, build obstacles and have powerful devil spellcasters at your side.

Origin of attacks is river Styx. How would you shape your defences or perhaps even complettely destroy the invaders? Redirecting rivers of lava? Setting up turrets that do thunder damage? Make dragon-like constructs that constantly strafe the river and invading forces with breath weapons, demons are not resistant to? Threat never ends and must be stopped or destroyed.

How far can one push this hellish "tower defence"? I am not familiar enough with the lore, but the most broken/logical/automated solutions are welcome.

Thanks!

[OldTrees1]

Answer depends on how the quantity and quality of the demon horde's magic.

Assuming some have flight but most don't:
Locate which way they are sailing up/down the styx. Maintain air superiority and hold the banks of the river. Use artillery to sink the ships. The goal is to let the river itself do the majority of the work.


Assuming at least the majority can fly:
Find the location they are entering from. Use long range AoEs against the core of the fliers. Have your minions mop up those that escape.

Assuming they can fly and are long range too:
Same as before but have your units be evasive and have the mop-up crew use long range.

Assuming they can gate to where ever they want:
Place scouts through Avernus. Gate into where they appear and take them out quickly.

[JackPhoenix]

The dark secret of the Blood War is that it doesn't really matter how you're fighting, as long as you do. Demons are technically endless, but every horde is finite. If the vast legions of lemures can't take them down, the artillery might. If they get through the trenchlines, they'll run into GoW minefields. If they break through one line of defense, there's another, and another, and yet more beyond that. Eventually, the horde will be grinded down, and you'll have time to fix the defenses and prepare new tricks before a replacement arrives to the same part of the front. Or maybe not, and it'll take centuries of millenia to retake the territory. The demonic generals may be brilliant tacticians, but they have to work with demons... their forces may be eager to fight, but they undisciplined, unreliable, prone to infighting, and probably haven't even heard of logistic or a long-term strategy. The scale of the conflict is unimaginable, the lines of battle are shifting constantly both ways. Even if the demons push deep into Avernus, there's more devil reinforcements marching from deeper below. The demons may outnumber the devils in an individual engagement, but neither side will fall to attrition. And the nature of the threat changes constantly, there's no single magical solution that can stop everything.

So feel free to do whatever you want. It will be inevitably countered, and then you'll have to come up with a new trick. Or not, because the next horde probably didn't get the memo, and it's not a swarm of vrocks big enough to overshadow continents, but a mixed horde of hezrous and dretches, and your defenses work on that. It probably won't work the time after that, but that's what the other defense lines are for.

[tKUUNK]

I would send my minions across the planes to capture angelic beings (including humanoids with angelic bloodlines) and bind / chain them in the path of the invading demon hordes. This would be a delightful source of entertainment for me.

[Unoriginal]

I would send my minions across the planes to capture angelic beings (including humanoids with angelic bloodlines) and bind / chain them in the path of the invading demon hordes. This would be a delightful source of entertainment for me.

There is no way in any Hells that your superiors would let you do that.

It would make Avernus a direct target for the heavenly forces. And *nobody* in Hell wants that.

[GloatingSwine]

There is no way in any Hells that your superiors would let you do that.

It would make Avernus a direct target for the heavenly forces. And *nobody* in Hell wants that.

Also if it was too successful they'll assassinate you for thinking of it first. Can't have your underlings standing out too much, lest they question why they are still underlings.

[Sigreid]

Also if it was too successful they'll assassinate you for thinking of it first. Can't have your underlings standing out too much, lest they question why they are still underlings.

I think I read in one if the books that Asmodeus is believed by some sages to be able to win the blood war whenever he pleases but it in some way serves his purpose for it to continue.

[Unoriginal]

...and were tasked to stop/push back/destroy endless demon hordes, constantly invading your hells. You are given vast armies that can fight, build obstacles and have powerful devil spellcasters at your side.

Origin of attacks is river Styx. How would you shape your defences or perhaps even complettely destroy the invaders? Redirecting rivers of lava? Setting up turrets that do thunder damage? Make dragon-like constructs that constantly strafe the river and invading forces with breath weapons, demons are not resistant to? Threat never ends and must be stopped or destroyed.

How far can one push this hellish "tower defence"? I am not familiar enough with the lore, but the most broken/logical/automated solutions are welcome.

Thanks!

No plan survives contact with the enemy, Demons are too chaotic to predict, and Devils are the kind to follow the textbook to the letter.

I think most Blood War battles are going to involves Lemures dying en masse to serve as sponge between the Demons and the Devil troops that are worth something according to the infernal hierarchy, with ranged options raining on the Demons while they're busy going through the Lemures and the other defenses.

I think I read in one if the books that Asmodeus is believed by some sages to be able to win the blood war whenever he pleases but it in some way serves his purpose for it to continue.

Some sages may believe it, but evidences point to the contrary.

Asmodeus cannot stop Demons from entering Avernus by the Styx, and he cannot conquers the Abyss and steal its might for himself either.

That means the only other way to "win" the Blood War he'd have would be to annihilate the Abyss, and he most likely cannot do that (or at least cannot without losing enough power it'd be a Pyhrric victory that'd leave him at the mercy of every other planar power who'll want their pound of flesh).

[GloatingSwine]

I think I read in one if the books that Asmodeus is believed by some sages to be able to win the blood war whenever he pleases but it in some way serves his purpose for it to continue.

By some sages that asked Asmodeus and weren't going to risk calling him a liar or fool...

Ultimately I suspect that the Blood War rages because it cannot be otherwise. Emanations of Chaotic Evil must attempt to destroy all things, emanations of Lawful Evil must attempt to control all things, and so conflict must occur wherever the two can meet in the presence of things.

That means the only other way to "win" the Blood War he'd have would be to annihilate the Abyss, and he most likely cannot do that (or at least cannot without losing enough power it'd be a Pyhrric victory that'd leave him at the mercy of every other planar power who'll want their pound of flesh).

Not just the abyss. Limbo and Arborea as well. He'd have to destroy the concept of Chaos so that only Lawful Evil could remain.

[NecessaryWeevil]

If the Styx is the point of entry....
What happens if you try to dam or redirect the river, I wonder?

[GloatingSwine]

If the Styx is the point of entry....
What happens if you try to dam or redirect the river, I wonder?

Swap it with the Lethe and all the demons forget why they are there and go home.

[Sigreid]

By some sages that asked Asmodeus and weren't going to risk calling him a liar or fool...

Ultimately I suspect that the Blood War rages because it cannot be otherwise. Emanations of Chaotic Evil must attempt to destroy all things, emanations of Lawful Evil must attempt to control all things, and so conflict must occur wherever the two can meet in the presence of things.



Not just the abyss. Limbo and Arborea as well. He'd have to destroy the concept of Chaos so that only Lawful Evil could remain.

I don't know man. The blood war keeps subordinates to busy to make a serious attempt to do a power grab and keeps the celestial powers to scared to go after him in a serious way. Wouldn't be the only dictator to keep a war going to make it easier to hold power.

[GloatingSwine]

Just because he benefits from the status quo doesn't mean he has the power to overturn it.

But being the top dog in a ruthless environment means he absolutely needs to pretend he does.

[Unoriginal]

If the Styx is the point of entry....
What happens if you try to dam or redirect the river, I wonder?

You get fired for wasting Hell's ressources on an impossible task, mostly.

Worth noting that the souls of lawful evil mortals also use the Styx as point of entry, so succeeding would mean cutting off Hell's main soul supply.

I don't know man. The blood war keeps subordinates to busy to make a serious attempt to do a power grab and keeps the celestial powers to scared to go after him in a serious way. Wouldn't be the only dictator to keep a war going to make it easier to hold power.

The Celestial powers aren't scared to go after Asmodeus. They're happy he's getting his dreams of planar conquests crushed by the Demons, though.

Also, while the Blood War has been convenient for Asmodeus a few times (since Asmodeus wouldn't be Asmodeus if he couldn't turn a disadvantage into a perk *some* of the time), it's pretty clear he doesn't need it to easily hold power, while it is the main reason why his ambitions do not work out.

[tKUUNK]

Ultimately I suspect that the Blood War rages because it cannot be otherwise. Emanations of Chaotic Evil must attempt to destroy all things, emanations of Lawful Evil must attempt to control all things, and so conflict must occur wherever the two can meet in the presence of things.

This is a well-stated perspective. Feels like an absolute truth.

On another note: devils being devils, every soul they can bribe, threaten, or otherwise contract into doing their dirty work, they will.

And one more thought - make use of teleportation areas or interplanar portals to redirect demon hordes. even if you just teleport them backwards a few hundred feet every time they cross a certain line.

[Sigreid]

You get fired for wasting Hell's ressources on an impossible task, mostly.

Worth noting that the souls of lawful evil mortals also use the Styx as point of entry, so succeeding would mean cutting off Hell's main soul supply.



The Celestial powers aren't scared to go after Asmodeus. They're happy he's getting his dreams of planar conquests crushed by the Demons, though.

Also, while the Blood War has been convenient for Asmodeus a few times (since Asmodeus wouldn't be Asmodeus if he couldn't turn a disadvantage into a perk *some* of the time), it's pretty clear he doesn't need it to easily hold power, while it is the main reason why his ambitions do not work out.

Or, it's just a statement I saw somewhere that's intended to wreath Admodeous in mystery and fear for game lore purposes.

[Witty Username]

Go on the attack, dying in Avernus is significant concern and demons slain in the abyss is future battles one, when defense is a needed absolutely, fortify and make any engagement a long-term ordeal. The greatest advantage to exploit against demons is they are not united, and even demon lords must fear eachother. The longer a fight takes a lord away from their holdings, the more risky it becomes. Use contracted mortals whenever possible when defending holdings, death is less of a concern as the hells will claim them in the end. Past that, whatever one needs to apear as they are not shirking, an angry Zariel is as much of a problem as a demon lord, and a displeased Asmodeous is worse.

[Segev]

As has been pointed out, dying in Avernus is the worst outcome for your forces; it is the only way they don't respawn as themselves. To that end, lemures are probably the only devils you consider truly expendable in this fashion; others, you either specifically want to survive (for their experience and loyalty) or specifically want to die (for the threat they pose to you as rivals or traitors).

Hire Yuogloth mercenaries to guard your first lines of defense, and put your devils to work on projects that make you the wealth the Yugoloths get paid in. Pay them generously, so they fear losing your employment bore than they crave any one-off bribe. Offer to match bribes that they accept if they tell you about them and betray the bribe payer to you. They may, of course, keep the payer's bribe.

Likewise, see what you can do about creating live capture methods, so the demons don't die in Hell. Take them to the devil-forges and transform them into weapons. Preferably highly-destructive one-offs. It is important they stay alive through this torturous process. Launch counter-attacks into the Abyss and blow up these one-off demon weapons there, ensuring their essence is reabsorbed by the Abyss and loses all experience and identity and can't come back as anything worse than a fresh recruit.

[JackPhoenix]

Hire Yuogloth mercenaries to guard your first lines of defense, and put your devils to work on projects that make you the wealth the Yugoloths get paid in. Pay them generously, so they fear losing your employment bore than they crave any one-off bribe. Offer to match bribes that they accept if they tell you about them and betray the bribe payer to you. They may, of course, keep the payer's bribe.

I'm sure nothing wrong can come from overly relying on mercenaries who have their own agenda and are betrayal personified, if you just pay them well...

Likewise, see what you can do about creating live capture methods, so the demons don't die in Hell. Take them to the devil-forges and transform them into weapons. Preferably highly-destructive one-offs. It is important they stay alive through this torturous process. Launch counter-attacks into the Abyss and blow up these one-off demon weapons there, ensuring their essence is reabsorbed by the Abyss and loses all experience and identity and can't come back as anything worse than a fresh recruit.

Sounds like a lot of effort wasted for little gain. Abyss doesn't work like Hells do, if it wants to create a balor, it will, no need to jump through any hoops to get promotions.

[noob]

As has been pointed out, dying in Avernus is the worst outcome for your forces; it is the only way they don't respawn as themselves. To that end, lemures are probably the only devils you consider truly expendable in this fashion; others, you either specifically want to survive (for their experience and loyalty) or specifically want to die (for the threat they pose to you as rivals or traitors).

Hire Yuogloth mercenaries to guard your first lines of defense, and put your devils to work on projects that make you the wealth the Yugoloths get paid in. Pay them generously, so they fear losing your employment bore than they crave any one-off bribe. Offer to match bribes that they accept if they tell you about them and betray the bribe payer to you. They may, of course, keep the payer's bribe.

Likewise, see what you can do about creating live capture methods, so the demons don't die in Hell. Take them to the devil-forges and transform them into weapons. Preferably highly-destructive one-offs. It is important they stay alive through this torturous process. Launch counter-attacks into the Abyss and blow up these one-off demon weapons there, ensuring their essence is reabsorbed by the Abyss and loses all experience and identity and can't come back as anything worse than a fresh recruit.

That and when possible fortify areas within the abyss: this is possibly a way to start turning them in more hell according to some planar theories but until it happens, it is areas where the death of your devils is temporary(still a few centuries) and where killed demons die for real.

[Unoriginal]

The Nine Hells do not have the means to start fighting in the Abyss.

Well, maybe they have the means, but they're not committing them to that.

Bel's plan to solve the Blood War problem was to fortify the important parts and let the Demons roam in the wastelands. That got him demoted.

[JackPhoenix]

The Nine Hells do not have the means to start fighting in the Abyss.

Well, maybe they have the means, but they're not committing them to that.

Bel's plan to solve the Blood War problem was to fortify the important parts and let the Demons roam in the wastelands. That got him demoted.

Correction: They don't have means to secure any significant gains in the Abyss. They are raiding it all the time. But unlike Hells that can only be accessed through Avernus (or magic), many (most?) Abyssal layers are open to visitors. That means it's impossible to establish anything resembling a frontline. Even if you manage to capture and hold some territory, it has next to zero strategic value, you won't stop the demons from simply going through other layers.

[Witty Username]

The Nine Hells do not have the means to start fighting in the Abyss.

Well, maybe they have the means, but they're not committing them to that.

Bel's plan to solve the Blood War problem was to fortify the important parts and let the Demons roam in the wastelands. That got him demoted.

Zariel replaced Bel because of how aggressive she is, and at least as far as I was aware she spends much of her time invading areas of the Abyss and contested planes in the Blood War, defense of Avernus is a priority (hold the dividing line), but offense is how one keeps favor with Zariel, that means scraping in the Abyss.
--
Invading layers does have strategic value by killing demons, and with great luck and skill demon lords. As well as disrupting power bases, ransacking draws ire, which promotes rashness, which demons are already prone too. Infighting is also a factor, Devils are beholden to Asmodeous (at least on paper, politics and rivalries happen, but no one is arguing who the ruller of hell is or if it has one), demons don't have even a semblance of unity beyond, don't start a fight you cannot win.

[Unoriginal]

Zariel replaced Bel because of how aggressive she is, and at least as far as I was aware she spends much of her time invading areas of the Abyss and contested planes in the Blood War, defense of Avernus is a priority (hold the dividing line), but offense is how one keeps favor with Zariel, that means scraping in the Abyss.
--
Invading layers does have strategic value by killing demons, and with great luck and skill demon lords. As well as disrupting power bases, ransacking draws ire, which promotes rashness, which demons are already prone too. Infighting is also a factor, Devils are beholden to Asmodeous (at least on paper, politics and rivalries happen, but no one is arguing who the ruller of hell is or if it has one), demons don't have even a semblance of unity beyond, don't start a fight you cannot win.

There's more than enough Demons in Avernus to keep most of Zariel's aggression in the first layer of Hell.

Unless I'm mistaken, there are at least three Demon Princes in Avernus during the DiA module, one of whom was personally defeated by Zariel and chained down in a pit.

Raids in the Abyss probably happen, but whoever is in charge better have stellar results if they don't want to get accused of wasting valuable time and troops when said things could have been deployed against the Avernus invaders.

[Witty Username]

Unless I'm mistaken, there are at least three Demon Princes in Avernus during the DiA module, one of whom was personally defeated by Zariel and chained down in a pit.

Raids in the Abyss probably happen, but whoever is in charge better have stellar results if they don't want to get accused of wasting valuable time and troops when said things could have been deployed against the Avernus invaders.

I am not familiar with the module, but to double check myself I just looked at the Forgotten Realms wiki pages for Zariel and Bel. I got the impression that Zariel is primarily focused on the Abyss with Avernus being primarily the focus to keep the River Styx held.

Then again, I am pretty comfortable being incorrect on that point. My familiarity with the Blood War is mostly Tome Of Foes.

I am more interested in planar mechanics and how that should inform tactics.

[JackPhoenix]

Invading layers does have strategic value by killing demons, and with great luck and skill demon lords. As well as disrupting power bases, ransacking draws ire, which promotes rashness, which demons are already prone too. Infighting is also a factor, Devils are beholden to Asmodeous (at least on paper, politics and rivalries happen, but no one is arguing who the ruller of hell is or if it has one), demons don't have even a semblance of unity beyond, don't start a fight you cannot win.

The issue is that killing demons doesn't matter much. Killing demon lords is highly unlikely, unless archdevils get involved personally (and even then, it's not enough to just physically kill him, demon lords do have the means to reform when killed, even in Abyss), and any lesser demons will just get replaced. Sure, the replacement may not have the same memory and personality, but that doesn't mean much, a balor is a balor. Any disruption caused will be temporary at best. Even centuries mean little for immortals.

[Witty Username]

The issue is that killing demons doesn't matter much. Killing demon lords is highly unlikely, unless archdevils get involved personally (and even then, it's not enough to just physically kill him, demon lords do have the means to reform when killed, even in Abyss), and any lesser demons will just get replaced. Sure, the replacement may not have the same memory and personality, but that doesn't mean much, a balor is a balor. Any disruption caused will be temporary at best. Even centuries mean little for immortals.

Centuries may be not worth much, but they are worth more than moments, banishing a demon from Avernus, is effort that is almost entirely wasted (as the demon will reform Instantaneously in the Abyss, and nothing is stopping them from going right back into Avernus while while you are recovering yourself and your forces) and very dangerous (you may be replaced immediately by a rival that was jockeying for your position, so the effect on the greater blood war will be small, but you the devil general, will be dead).
This is why devils employ Yoguloths at all, despite how treacherous they are, death is a real possibility to be avoided at all costs and extraplannar mercenaries don't have this problem.