How to guard a teleportation circle

[RangerWickett]

In 4th edition, you can't just teleport willy-nilly. You can only go to pre-assembled teleportation circles, which are activated by performing a ritual. It would make sense that large cities would have one; they're very handy when used by friendly people. But how would you defend one to prevent hostiles from easily attacking your city?

Mind you, it costs a few hundred GP to open the portal for less than 30 seconds, so you can't march an army through. But you don't want the circle in a public square so some jack-*** can teleport monsters in to attack during a nice happy picnic.

Say you're the mayor of a fantasy city. How do you design your teleportation circle to keep your city safe?

 

[Dioltach]

Build it indoors or underground, limiting the means of leaving the circle. Set a glyph to trigger an alarm if more than a certain number of creatures come through at one time, or if a powerful creature comes through. Have a contingency spell set so that anyone not leaving the circle through the official gate within an X number of rounds is immediately returned to their point of origin (possibly with a Delayed Fireball attached).

 

[Umbran]

There's several options:

1) Put the permanent circles outside the city. Make those coming in by the circles enter the city gates like everyone else, so that the same security that protects against overland invasion also applies to those who come in by the circles.

2) Put the permanent circles in guarded depots - basically, make a teleport station that you can guard as if it were a city gate, with the portal in a big stone room that has only one exit.

 

[Wycen]

In our Pathfinder game, one of the world conceits are teleportation circles built by the great civilizations that preceded the apocalypse that destroyed most our continent. Once you "control" one, you can use it to move to another teleportation circle under your control, it just takes some residuum to activate. Controlling one is done through a bit of handwavium and a skill check. See below for gaps in this system.

In our case, we built our headquarters around one. Some cultists were using a teleportation circle inside a warehouse and when we ended up taking out their forces in the OTHER end of the circuit, they burned down the warehouse inside town and the spot was granted to us by the king. We didn't know the teleporter was there, and the king probably didn't either. At least, that's how I'm remembering things, maybe we knew it was there and that's why we asked for the spot.

Anyway, the general public doesn't know it exists.

Beside being behind closed doors, we built an iron wrought staircase leading up to the 2nd story around the perimeter to funnel any unfriendly forces toward one hemisphere. That hemisphere is guarded by a golem we acquired and programmed to attack anyone it doesn't recognize. I think maybe they'd have to say a pass word, I'm not sure how the DM sees this working.

We may in fact find out soon since a portion of the circuit was tampered with in our last session and we ended up taking a short, as in 4 month trip in real time, surprise trip to the fairy realm. So clearly, you need live eyes and ears watching and guarding your teleporters.

 

[Janx]

Umbran's suggestion seems pretty straightforward for a gate system that doesn't have its own security protocols.

I have no clue how 4e works, but I'm inclined to envision something like how StarGate works.

you can't just walk into a circle and go to another circle. How would it know where you want to go. So each circle needs to be wired specifically to one other circle OR, the network needs an addressing mechanism to indicate which portal you want to go.

With the former in place, 2 circles are just like 2 doorways. Secure them with guards and a building, and nobody's getting from A to B

With the latter in place, just because you have Circle A doesn't mean you can get to my circle C. You'd need to know it's phone number (name, address, whatever you want to call it). Keep your circle's number a secret and nobody's going to beam in on it.

Another problem to solve is concurrency. In StarGate, the gate is an open portal when it's connected to another gate. So a third gate gets a busy signal when somebody tries to dial in when other folks are in the way.

You want to prevent telefragging, so this thing should not let incoming ports from another circle UNLESS the platform is empty. That also means that if you want to block incoming ports, put something on the platform, but don't initiate a teleport.

 

[Wycen]

Teleportation is generally a duration of "Instantaneous", but star gates seem to have a 47 minute duration, so I don't see open circuits being much of a problem.

 

[Janx]

Teleportation is generally a duration of "Instantaneous", but star gates seem to have a 47 minute duration, so I don't see open circuits being much of a problem.

In stargate, that's how long the doorway stays open. That's not the problem I'm talking about, so much as the nature of the stargate coincidentally solves it.


On a teleport pad, there's time before and after the teleport to load up people on the pad and for them to exit the pad before the next teleport comes in.

Not that this load and unload takes a lot of time, but the risk increases as the people dawdle on the pad longer and the pad usage frequency increases.

Without a blocking mechanism, you have a transporter accident waiting to happen.

I deal with this in computer software all the time as lazy developers rationalize not bothering to protect against this kind of thing because "sure it's possible, but it'll never happen that two things will try to consume the same resource at the same time, because it's rarely used"

Considering all it takes to prevent is adding "the circle will not accept an incoming teleport if the circle is not empty of non-air objects, and the circle will not send out its occupants if the destination circle is not clear" to the description text.

If magic is as complex (or more) as software development to make a teleport network, they can easily solve this important problem with some simple text for the description of how teleport circles work.

 

[Janx]

Teleportation is generally a duration of "Instantaneous", but star gates seem to have a 47 minute duration, so I don't see open circuits being much of a problem.

In stargate, that's how long the doorway stays open. That's not the problem I'm talking about, so much as the nature of the stargate coincidentally solves it.


On a teleport pad, there's time before and after the teleport to load up people on the pad and for them to exit the pad before the next teleport comes in.

Not that this load and unload takes a lot of time, but the risk increases as the people dawdle on the pad longer and the pad usage frequency increases.

Without a blocking mechanism, you have a transporter accident waiting to happen.

I deal with this in computer software all the time as lazy developers rationalize not bothering to protect against this kind of thing because "sure it's possible, but it'll never happen that two things will try to consume the same resource at the same time, because it's rarely used"

Considering all it takes to prevent is adding "the circle will not accept an incoming teleport if the circle is not empty of non-air objects, and the circle will not send out its occupants if the destination circle is not clear" to the description text.

If magic is as complex (or more) as software development to make a teleport network, they can easily solve this important problem with some simple text for the description of how teleport circles work.

 

[Stormonu]

Underground, with 100 tons of stone suspended overhead by a frayed rope - and a few guards standing near said rope with razor-sharp halberds.

Or a naquadra iris 1/16" away from the surface of the portal.

 

[Fiddleback]

So you aren't worried about a teleporting army, but rather random asshattery and the odd monster...

Fair enough.

Build a stone walled maze with only one exit and the teleporter in the center. A sufficiently complex maze will allow time to assess and prepare for the threat and the maze itself should prevent anything nasty from presenting an immediate threat to the general populace. You could probably cover the maze and teleporter with a net of some description to prevent climbing and flying threats.