Question about Keyed Portals

[Melcar]

Im planning of buiding a portal in my tower, which has to be in a hidden closet. I want it to link to my wault, which will contain magical laboratories, an archive of ancient text or secret texts, which does not need to be accessed by everyone, a treasure room for stuff like the nether scrolls or the grand staff, or ring of winter... stuff like that.

Now my tower is guarded by 18 guards, 3 sergeants, 1 officer, and 1 mage. Now I also plan on having a mithral golem and a runic guardian keyed to the tower, which activates on certain command words, by certain members of the watch. The officer and the 3 sergeants.

The wault (a sealed off underground lair, will only be accessible by the portal, so I want it to be very difficult to access this portal.

Now according to page 60 of FRCS, it says that the "key" can be a lot of things: Name, identity, alignment, rare and unusual object caried, particular times/seasons, the ability to channel positive or negative energy or spells.

My question is what is the most reliable key? I mean could identity be forged, by transmutation spells? Or would an object be too easy to identify and steal for rogues? What would you all suggest?

My own thougts was developing a spell in secret, which had a drop of blood as material or focus... like a DNA test on the spot, which had a duration of 1 round, just enough to cast and then step through.

Thanks!

[Max Caysey]

I think a custom spell, for that specific portal, which has a special, dificult to uptain, focus, is going to be the most secure.

[Phelix-Mu]

Don't use DNA. In addition to it arguably not being a thing in-setting, it also, if it exists, can likely be forged all kinds of ways. The most obvious abuse is that, if the spell component is a drop of your blood, then it's a non-valuable component, and is in every spell component pouch ever. If you word the spell carefully, you may be able to avoid that particular bit of particularly ridiculous RAW, but I daresay there are others.

So, my basic suggestion is to use a multi-part key, though your custom spell idea is pretty cool.

Basically, have a magic item be the key. This magic item is programmed to detect a magical device inside your body, or something like that. When the magic item senses it is being held by the right person, it changes it's shape/color/form/etc to match the form it had when it was attuned to the portal.

Cut yourself open with magic, tattoo a magical sigil of some kind on the inside of your skin, use some magic to cloak its aura, sew yourself back up. Ice assassin yourself, ice assassin the ice assassin, have the second ice assassin erase the memory of making the tattoo from your mind. Destroy the ice assassin.

Now you don't even know exactly how the key works, just that it works, and thus you can't be probed for the answer (except superior magic can probably undo even this). In hands besides yours, the key is the wrong shape/color/whatever, and thus doesn't work.

You can actually extrapolate this even further, but eventually it's diminishing returns, with increasing chances of something going wrong or unanticipated vulnerabilities emerging.

[Melcar]

Don't use DNA. In addition to it arguably not being a thing in-setting, it also, if it exists, can likely be forged all kinds of ways. The most obvious abuse is that, if the spell component is a drop of your blood, then it's a non-valuable component, and is in every spell component pouch ever. If you word the spell carefully, you may be able to avoid that particular bit of particularly ridiculous RAW, but I daresay there are others.

So, my basic suggestion is to use a multi-part key, though your custom spell idea is pretty cool.

Basically, have a magic item be the key. This magic item is programmed to detect a magical device inside your body, or something like that. When the magic item senses it is being held by the right person, it changes it's shape/color/form/etc to match the form it had when it was attuned to the portal.

Cut yourself open with magic, tattoo a magical sigil of some kind on the inside of your skin, use some magic to cloak its aura, sew yourself back up. Ice assassin yourself, ice assassin the ice assassin, have the second ice assassin erase the memory of making the tattoo from your mind. Destroy the ice assassin.

Now you don't even know exactly how the key works, just that it works, and thus you can't be probed for the answer (except superior magic can probably undo even this). In hands besides yours, the key is the wrong shape/color/whatever, and thus doesn't work.

You can actually extrapolate this even further, but eventually it's diminishing returns, with increasing chances of something going wrong or unanticipated vulnerabilities emerging.

The plan was to have the spell cast still and silent and then perhaps the blood from the caster (my character specifically) being a focus not material, since correct, that is in every spell component pouch. I do however think that some rare focus would be needed for the spell, and the spell it self, would be developed in as much secrecy as possible.

[Phelix-Mu]

The plan was to have the spell cast still and silent and then perhaps the blood from the caster (my character specifically) being a focus not material, since correct, that is in every spell component pouch. I do however think that some rare focus would be needed for the spell, and the spell it self, would be developed in as much secrecy as possible.

I still think that's not necessarily a good idea. If someone does get into the character's head, they get the key to the portal potentially.

Also, I'm pretty sure there is a 3.5 version of the spell Alamanthor's return, which copies a spell that the caster has just observed being cast. I don't know if that couples with scrying, but I find generally that, since you have to know the spell, it's fairly easy for others to copy it.

Just like passwords on computers, the best way to increase security is through multiple layers or multiple interlocking parts. If it's just one secret, it's not that hard to copy (because magic in 3.5 can do virtually anything).

Also, wish can copy other spells. So can limited wish, miracle, and possibly anyspell. I don't think there is any exception given to custom spells. Thus, ostensibly someone could come up and wish a copy of the spell, and it would grant entrance. Your blood focus might work to prevent some or all of these, but I'm not even sure it's that hard for someone else to get your character's blood.

Also, hypercognition and metafaculty powers would probably both turn up the answer to how to get in the portal, if not the spell itself. Of course, metafaculty in particular can reveal almost anything about anything, so trying to keep any secret is unlikely if you face all the possibilities of RAW. Hopefully the DM just won't think or will choose not to have the enemy be quite so resourceful.

In any case, I at least would suggest another layer of security, maybe one that your character can figure out, but can't know in advance, like some kind of morphing puzzle trap that must be disarmed first to get to the portal.

[Melcar]

I still think that's not necessarily a good idea. If someone does get into the character's head, they get the key to the portal potentially.

Also, I'm pretty sure there is a 3.5 version of the spell Alamanthor's return, which copies a spell that the caster has just observed being cast. I don't know if that couples with scrying, but I find generally that, since you have to know the spell, it's fairly easy for others to copy it.

Just like passwords on computers, the best way to increase security is through multiple layers or multiple interlocking parts. If it's just one secret, it's not that hard to copy (because magic in 3.5 can do virtually anything).

Also, wish can copy other spells. So can limited wish, miracle, and possibly anyspell. I don't think there is any exception given to custom spells. Thus, ostensibly someone could come up and wish a copy of the spell, and it would grant entrance. Your blood focus might work to prevent some or all of these, but I'm not even sure it's that hard for someone else to get your character's blood.

Also, hypercognition and metafaculty powers would probably both turn up the answer to how to get in the portal, if not the spell itself. Of course, metafaculty in particular can reveal almost anything about anything, so trying to keep any secret is unlikely if you face all the possibilities of RAW. Hopefully the DM just won't think or will choose not to have the enemy be quite so resourceful.

In any case, I at least would suggest another layer of security, maybe one that your character can figure out, but can't know in advance, like some kind of morphing puzzle trap that must be disarmed first to get to the portal.

Just to go a little bit more into detail. The portal itself, will be build into a sealed of section of the tower (wall all around) and will be heavyly warded. I will then create a permanent phase door (http://dndtools.eu/spells/players-handbook-v35--6/phase-door--2416/). That would mean that someone would have to penetrate mordenkainen's private sanctum/ (http://dndtools.eu/spells/players-handbook-v35--6/mordenkainens-private-sanctum--2340/), inscription of privacy and lead lined walls. So Someone will have physically seen the portal or seen my (my character) enter the phase door. In addition to the above mentioned i have Consecrate (http://dndtools.eu/spells/players-handbook-v35--6/consecrate--2596/), Forbiddance (http://dndtools.eu/spells/players-handbook-v35--6/forbiddance--2321/) (tokens) and Hallow (http://dndtools.eu/spells/players-handbook-v35--6/hallow--2619/) (Invisibility Purge), Greater alarm (http://dndtools.eu/spells/spell-compendium--86/alarm-greater--3824/). These wards permiate both my personal chamers and the secret, sealed portal chamber.

And lastly my character has an item that grands Mind Blank, as a continues effect.

My spell book is heavily incrypted, and warded.

I believe for wish or alamanthers return to dublicate a spell it has to be seen or at least know in such a way, that the enemy could ask for that particular spell. If he/she does not know that it is a spell which is needed as the key, then at least two wich must be cast. One for the knowledge of, that the key is a spell and then a wish to get that spell. And then of cource he would have to be at the portal.

[Max Caysey]

You could use a Rogue Stone as the focus for the spell. These are very rare magical gem stones which would then mean, that not only would the intruder need to know you had this secret portal, but he would need to get access to is, and then know that the key is a spell, which then would need an extremely rare gem.

Personally I think that Rogue Stones fit perfectly.