D&D 5E Preventing Teleportation

[Lord Vangarel]

The characters are infiltrating the fortress of a powerful cabal of wizards, but I don't want them to simply teleport or dimension door either into or out of it.

Is there a way within the rules to prevent this type of magic from working?

 

[steeldragons]

I believe Mordenkainen's Sanctum thwarts teleporting in.

Either Consecreate or Hallow (does 5e still have both?) does for clerics/druids as well...I think...or I may be misremembering.

Naturally a little Planar Bindings sprinkled here and there..."built into" the structure would do the same thing...but then might also thwart those trying to teleport out...but then, you're the DM [I presume] you can make the building, a single floor, individual chambers or the whole structure "one way" teleport proof...just because you say so...use Planar Binding rituals as a justification if the Sanctum spell is too high level.

 

[Lackhand]

Technically, teleport requires familiarity and can't cross planar boundaries.
The former prevents teleporting in, since the players just won't know about the interior.
The latter can stop ingress and egress cold: have enough planar bleed from something suitable and you can claim -- straightfacedly -- that they're on a different plane, and so cannot teleport.

Finally, I always buck the rules on this point. You can teleport out easy, but scrying isn't enough to establish familiarity.

 

[aramis erak]

I believe Mordenkainen's Sanctum thwarts teleporting in.

Either Consecreate or Hallow (does 5e still have both?) does for clerics/druids as well...I think...or I may be misremembering.

Naturally a little Planar Bindings sprinkled here and there..."built into" the structure would do the same thing...but then might also thwart those trying to teleport out...but then, you're the DM [I presume] you can make the building, a single floor, individual chambers or the whole structure "one way" teleport proof...just because you say so...use Planar Binding rituals as a justification if the Sanctum spell is too high level.

Antimagic field (8th level, Wizard and Cleric) also blocks teleportation and planar travel.
Hallow, yes. 5th level. Cleric only. Blocking planar travel and teleportation (jointly) is one possible effect.
Consecrate, no. Rolled into Hallow.
Mordenkainen's Sanctum is 4th level, Wizard only. It can, if the caster wishes, prevent teleportation into and within. It can also (separately) block planar travel.
Forbiddance (6th level, Cleric) protects 40,000 square feet (1600 standard 5' squares, or a 200' x 200' area) to 30'...

 

[jrowland]

Another fan-favorite is to make the walls "magic", preventing teleport without the "key".

 

[Sunseeker]

You attempt to open a portal, but your spell fizzles, what do you do? (hopefully someone trained in magic does something to figure out why).
Pick a reason. "They're incredibly powerful wizards and have littered the castle with magical wards preventing teleportation." Perhaps the party will find a way to alter the runes to prevent anyone from teleporting in or out, but doing so could alert patrols to their presence (arcana check to determine how inconspicuously altered).
Or quite simply: You can guess where you're teleporting to, you might teleport into a wall, or a pit, or another person, but if you don't know exactly where you want to go, you need to make a high DC check to "guess right".

 

[Lord Vangarel]

Thanks everyone for the replies. I'll investigate and make some decisions. I think a cabal of wizards should prevent someone just teleporting in or out as a matter of course, if they can't then who can?

Also didn't want to go down the DM says so route on this one as players likely to call me on it as a means of preventing them escaping once they've done their mission.

 

[Rabbitbait]

Thanks everyone for the replies. I'll investigate and make some decisions. I think a cabal of wizards should prevent someone just teleporting in or out as a matter of course, if they can't then who can?

Also didn't want to go down the DM says so route on this one as players likely to call me on it as a means of preventing them escaping once they've done their mission.

DM says so is fine, as long as it is well in advance. Not so good if they plan their escape well in advance with teleport as an essential part and you spring it on them when they cast the spell.

"Sorry guys, the teleport didn't work. There must be some sort of teleport protection or something. Looks like a TPK for you."

 

[Lord Vangarel]

DM says so is fine, as long as it is well in advance. Not so good if they plan their escape well in advance with teleport as an essential part and you spring it on them when they cast the spell.

"Sorry guys, the teleport didn't work. There must be some sort of teleport protection or something. Looks like a TPK for you."

That's just it, they've fled to the dungeon area below the wizards mansion with the idea they're going to just teleport out to escape. I've always had it in my mind that teleporting in and out should be prevented by the wizards but as it's essentially a surprise on the characters it has to be strictly by the rules. Either that or I just let them do it and carry on.

 

[IgnatiusJ.Reilly]

There was spell in 3rd edition 'Dimensional Anchor', but I can't remember how large an area it could ward.