please poke holes in my idea

[Eben]

I'm working on a meta-plot idea and I want to check if it can stand up to scrutiny. Here goes:

Magic only works in a geograhical limited area of the world. The reason is that certain structures tap into the otherworldly magical energies and emmit them over limited radius. It is possible that these emissions are enhanced by certain natural geographical features (valley's, rivers, ...) Currently there is only one such working structure. Knowledge of this has been lost a long time ago and the majority of the world believes magic is something from fairy tales.
During the campaing the PC's will find clues that magic used to be available all over the world.

Some otherworldly race found out about this place where magic is virtually non-existant and they set up a number of portals that will provide them physical acces and a means of transmitting their own magical energies to this world so they can enslave the population and extract the worlds resources.

PC's will have to find a way to reboot the magical transmission system so that the mages that still exist (focussed around the last structure (I'll call it an oracle)) will be able to defend more efficiently against the invasion.

That's the very broad outline. Any points where this could crash?

Peter

 

[Lockridge]

Aliens aren't exactly a preferred flavour of mine but personal opinion aside I think its an overall good idea. Usually, crashes occur in the details and your post can't give out too many details without it being too long.
In order for the alien portals to exist, they would likely have to set them up near the magical structures on your PC's homeworld. Therefore the aliens would have to overcome the mages who exist at those locations.
Any mages that exist are likely very weak and would likely be easily overcome by a magic-using race. Making that believable would be a big hurdle for you. Perhaps instead of defending against the invasion, your PCs should be tasked with simply destroying the alien portals using any existing magic or brute force. When the portals are destroyed the aliens are cut off without reinforcements or supplies.
You can even make your PCs face a difficult decision - it may be that the only way to destroy these portals (which are powered by magic) is to destroy the magical structures in the world. This would mean the effective loss of magic in your world for generations. Of course you could make it possible for a smart PC to find a way around this.
Another crash may be the fact that the players in your group would not wish to play spellcasters. If I were a player I'd be afraid that the DM may isolate me from my powers by sending me away from the magic structures, thereby making my character useless.
Just some thoughts. Good luck with your campaign.

 

[diaglo]

all magic? divine and arcane?

why not abandon such a place? if other worldly creatures can enter, then can't the inhabitants leave thru those portals?

 

[Bardsandsages]

Magic only works in a geograhical limited area of the world. The reason is that certain structures tap into the otherworldly magical energies and emmit them over limited radius. It is possible that these emissions are enhanced by certain natural geographical features (valley's, rivers, ...) Currently there is only one such working structure.

If magic doesn't work anywhere, then how did anyone make a structure to tap into otherworldly magical energies to begin with? The premise falls apart at square one.

Now assuming that magic existed all over your planet at some point, then the real question is "Where did it go, and why is it still in a certain location?" This all depends on a lot on your total mythos. Did the gods all kill each other and their deaths created massive dead magic zones, but the god that lived in this one area simply went into hibernation and therefore the area remained pure? Did one god banish all the others and simply surpress magic, but a secret cabal of worshippers were able to somehow protect this one area? I suppose this is what I need to know first before I can consider the rest of the idea.

 

[Eben]

I wasn't thinking aliens, but something from the planes. Perhaps demons or devils, I still have to look through a few monster books to find something interesting. But that's a detail imo.
I like the idea of destroying the oracles! As for the weak mages... There would be only one working oracle, localized in a peripheral part of the world, extending it's magic over the land where the PC's live: a young federation that has only resolved it's issues with one another recently, whith scars still existing and only now starting to look outward to the rest of the world. (Talk about bad timing!)
I'dd cut of divine magic as well: even the gods need conduits to send their power. As to leaving: you'd have to be able to create portals, they would not be pre-existing.

Peter

 

[Umbran]

That's the very broad outline. Any points where this could crash?

Without reading the others (to perhaps give an idea of what is really obvious) -

1)Both the attackers have a major problem: they can only use magic near their own access points - the only place they can go on the offense is near a place that it tactically important for them to defend. Expansion becomes difficult when your best tools don't work where you're trying to occupy. And, of course, the defenders get to know the general location of the attacker's bases - if they can use magic, it is nearby.

2)The defenders, having one and only one major site, near which the attacker's magic works, should be incredibly easy to squash. Sort of having only one ammo stockpile, stuck out where the enemy can come and use it to shell your base with...


Now, reading some of the others:

If magic doesn't work anywhere, then how did anyone make a structure to tap into otherworldly magical energies to begin with? The premise falls apart at square one.

Well,the same can be said for any industrial infrastructure. There has to be some bootstrapping. If the structure doesn't require magic to create it's fine. At some poiont, either nature or mundane labor created the first sites, and someone figured out how that worked so they could build more.

 

[wedgeski]

Funny how DM's minds work... my upcoming homebrew works on a very similar premise (magic limited to within a radius of critical structures).

I prefer your 'reboot the magic' idea rather than destroying the oracles, although of course there's bound to be people on both sides of the question. Those seeking a return to the legendary days of yore want to restart magic; those who like the status quo will want to destroy it.

Also, how about if the portals generated by this invading force work fine on their side, but warp and sputter on the non-magic side, which has consequences for the invasion somehow? Perhaps the beings are made insane by coming through, or perhaps they are simply cut off (at which point their entire agenda would probably change).

Good luck!

 

[Eben]

As to restoring the magical energy, I'dd like to make it a mechanical thing, but not on this plane, but on the plane that fuels the structures. Perhaps staging a war in the heavens with the pantheon of the players world defending their last refuge agains the hordes of chaos. (Maybe I should use the same invaders...). Makes for some interesting high level play: fighting side by side with the gods...

Peter

 

[Eben]

Also, how about if the portals generated by this invading force work fine on their side, but warp and sputter on the non-magic side, which has consequences for the invasion somehow? Perhaps the beings are made insane by coming through, or perhaps they are simply cut off (at which point their entire agenda would probably change).

Good idea! This will give me a handle to slow down or advance the invasion, making this a bit more believable.

Peter

 

[BSF]

You might be able to avoid the plot hole that bardsandsages brings up if you use psionics. The invaders utilize psionics and are very appreciative of a world where arcane and divine magic cannot stand in their way right now. This gives the PCs more options. They could encourage the world to embrace psionics, or they could attempt to recover how magic used to work.