Good techniques against invisible, shapechanging infiltrators?

[Coidzor]

So I'm currently having to defend a mountain-fortress with a cavern/basement with an entrance that it's currently unfeasible to seal off or modify with a gate or gatehouse.

I've got a tribe of minions living down there, tending to the various guardian monsters and acting as lookouts, and some form of invisible creatures killed a pair of them and took on their forms to scope out the cavern level and the tribe's village.

They seem to have stopped trying to kill minions after starting to send them out in groups of 4 or more, but I naturally want to tighten up my defenses against them or even, ideally, be able to lay a trap for them or seek them out and destroy them.

From what I've gathered, the creatures don't have flight, so there's that at least. They also don't seem to have any interest in trying to infiltrate the other entrances to our base, which do have gates.

We're currently an 8th level party, and we have access to 4th level Wizard and Shaman spells and 2nd level Antipaladin and Inquisitor spells. All either LE or NE. We've got about 40,000 gp to bring to bear, though I'd naturally prefer to not spend all of our money on this project.

So far the idea of making some simple and cheap Flour traps has been brought up, as has been making a Lantern of Revealing.

I could get an Imp with constant Detect Good and Detect Magic with Lesser Planar Ally, but I'm not quite sure how to employ it or what to task it with.


I'd also love to be able to track them down, but our base is surrounded by a thick forest and half the group is convinced that even attempting it would just be a snipe hunt. Currently I can only manage around a +18 or so Survival check while buffed up, too, +14 is the best I can put up for all day, +16 the best for most of the day.

[Telonius]

Bacon grease trap, gives them a nice strong smell. Get a bloodhound, and you're off to the races.

[Coidzor]

Bacon grease trap, gives them a nice strong smell. Get a bloodhound, and you're off to the races.

Ooo, a stank trap. Niiiiice! :smallbiggrin:

[Geddy2112]

I second mundane scent traps, it should make tracking them a bit easier. Or any kind of marker dye that is hard to wash off. Leave poisoned food or marked items for them to steal, then locate object. If you have a part of the intruders, you can always attempt to scry on them and gain info. Perhaps cast speak with animals/plants near the entrance and ask for info. Likewise, commune with birds might give you an answer. If the shaman had 5th level spells you could commune with nature and ping your visitors.

Have you tried digging a pit trap or some other thing? Even a tripwire.

Set an alarm spell warding the choke point and wait for it to be set off. Tell the minions the password or ban the minions from entering/leaving that way. If you had the ability to cast it, glyph of warding with a powerful damage spell(fireball or something) attached would be the ticket. You could even have it be glitterdust and wait for the things to pass, be hit with the glitterdust, and then pick them off.

[Ellrin]

Custom magic trap using detect magic, glitterdust, and invisibility alarm built near the entrance. Forget passwords, with a certain number of minions of low Int, a password system becomes too complicated to deal with. With detect magic and invisibility alarm as your base, every time the trap detects an invisible creature or creature under a magical polymorph effect, the creature is affected as though by glitterdust. You could combine it with the mundane stink trap that's already been discussed so the spellcasters can't just dispel the effect, too.

Add some tar and feathers into the mix and your invisible and/or polymorphed guests should have a very hard time staying unnoticeable.

[Braininthejar2]

doorways with bead-string curtins.

pets with blindsense.

[Coidzor]

So, good news is, I found out what they were. Moon Dogs.

Bad news is, we only managed to kill one of the two that ambushed us in the woods, although we slaughtered the rest of the encounter and the Lillend that we believe was their boss.

Kind of amusing to see Good Outsiders just callously sending people to their deaths, though.


I second mundane scent traps, it should make tracking them a bit easier. Or any kind of marker dye that is hard to wash off. Leave poisoned food or marked items for them to steal, then locate object. If you have a part of the intruders, you can always attempt to scry on them and gain info. Perhaps cast speak with animals/plants near the entrance and ask for info. Likewise, commune with birds might give you an answer. If the shaman had 5th level spells you could commune with nature and ping your visitors.

Have you tried digging a pit trap or some other thing? Even a tripwire.

Set an alarm spell warding the choke point and wait for it to be set off. Tell the minions the password or ban the minions from entering/leaving that way. If you had the ability to cast it, glyph of warding with a powerful damage spell(fireball or something) attached would be the ticket. You could even have it be glitterdust and wait for the things to pass, be hit with the glitterdust, and then pick them off.

Did not manage to get any pieces of them, and Commune with Birds turned up nothing, I think because they just stay invisible 24/7.

They managed to bypass a number of pit traps and tripwires and several glyphs of warding.

I suppose now I can afford to have a 24/7 cycle of Alarm spells up to cover the various entrances, yeah.


Custom magic trap using detect magic, glitterdust, and invisibility alarm built near the entrance. Forget passwords, with a certain number of minions of low Int, a password system becomes too complicated to deal with. With detect magic and invisibility alarm as your base, every time the trap detects an invisible creature or creature under a magical polymorph effect, the creature is affected as though by glitterdust. You could combine it with the mundane stink trap that's already been discussed so the spellcasters can't just dispel the effect, too.

Add some tar and feathers into the mix and your invisible and/or polymorphed guests should have a very hard time staying unnoticeable.

Ooo, I like it. Tar and feathers is a wonderful addition, thank you. Wouldn't have thought of the Invisibility Alarm as the trigger for a followup trap.


doorways with bead-string curtins.

pets with blindsense.

Heh. Yeah, some bead curtains might just be a good idea.

Any forest, marsh, lake, or river creatures lower than CR 5 that you might recommend?

[Florian]

@Coidzor:

I think it´s high time that you actually post the rules for your campaign. How do you generate income/WBL, how are things like traps and minions factored in WBL, is leadership a factor and how does your gm price hiring minions and on what basis are they available? Are custom traps and such a thing for your table and if yes, what kind of sources are available and how lenient is your gm with interpretation of the rules?
I´ve got the feeling that you will ask more questions for your Dungeon Keeper campaign and these things should be clear.

[Braininthejar2]

Any forest, marsh, lake, or river creatures lower than CR 5 that you might recommend?

Obviously bats. Other creatures if you can argue with a DM - animals are badly understatted in 3.5 as far as ex abilities are concerned.

(example - an owl has hearing sharp enough to pinpoint and kill a mouse tunneling under snow)

[Frosty]

Here's how my group dealt with the moon dogs: we spent a week giving our minions "Anti-infiltration training 101". Basically, passcodes that change daily (think Tarkin style security measures), and also made all patrol groups memorize the looks and names of each other. Lastly, each group carried at least one bag of flour at all times.

The moon dogs didn't stand a chance. No one out-Balentynes the PCs!

[Braininthejar2]

Here's how my group dealt with the moon dogs: we spent a week giving our minions "Anti-infiltration training 101". Basically, passcodes that change daily (think Tarkin style security measures), and also made all patrol groups memorize the looks and names of each other. Lastly, each group carried at least one bag of flour at all times.

The moon dogs didn't stand a chance. No one out-Balentynes the PCs!

DO you have a campaign journal anywhere?