Protection against an aboleth's enslave ability

Question

I am structuring the first part of my campaign and have decided the big bad is an aboleth. However supporting the aboleth will be a wizard, who has sought the creature out and is willing to work for it in return for the knowledge and power it can give him. This wizard will be lawful evil but acting as a friend, confident and ally.

What I am looking for is a way for this NPC to protect himself from the aboleth's ability to enslave (he has researched and read about them and is prepared). This is his insurance to ensure his pact with the aboleth is 2 way.

What magic items or spells available to a wizard would allow this protection?

In game he is living in a town 5-6 days travel from the aboleth and visits it only when needed to discuss progress and the next stages of the plan, or take individuals to be enslaved.

A magic item would be preferable as it would allow the players to gain an advantage for when they finally find and face the aboleth itself.

The players will be interacting with this wizard from level 1-6 initially as an ally but I am happy making him a higher level enemy and so giving him high level spells if appropriate, I can have him avoid direct confrontation and instead try and escape. Or the players come up with interesting ways to try and defeat him that don’t require direct combat if necessary if he is too high a CR to face directly.

Answer 1

This wizard needs complete immunity to the aboleth's ability

Based on what you've described, something that gives a simple bonus to or advantage on saving throws isn't going to be sufficient. Every time the wizard visits the aboleth, the aboleth will get 3 chances to enslave him, so he will want to leave nothing to chance. This means that the wizard must accept nothing less than complete protection against the aboleth's enslavement.

I don't see any items that will do the job

There are a few magic items that can end the charmed condition under certain circumstances, but these will not be able to reliably end the aboleth's enslavement, because the aboleth will not allow the wizard to use them while enslaved. It might work once or twice while the aboleth is unaware of the item, but an aboleth is smart and will catch on quickly.

There is the Staff of the Forgotten One, which confers immunity to charm among other things, but the staff is an artifact, it is canonically in the possession of a specific legendary undead, and it has some... let's say not insignificant downsides. This probably isn't something you want to potentially let fall into the hands of a low-level party, unless you want to cause a TPK. There is also a Greater Silver Sword, but this is a legendary +3 weapon with a special ability involving the astral plane -- again, probably not appropriate for levels 1-6.

A few wizard spells can help here

As other answers have pointed out, Mind Blank makes one creature immune to the charmed condition (not to mention all the aboleth's telepathic abilities) for 24 hours, no concentration required. This is clearly the superior solution, but it is also an 8th level spell, which means your level 1-6 party isn't going to have access to it unless you give it to them somehow. There is also the 6th level spell Tasha's Otherworldly Guise, which can grant immunity to the charmed condition (among other benefits) for 1 minute, concentration required. This would be sufficient for a short conversation, but little else.

However, there is one other suitable spell in this specific case, because the aboleth happens to be an abberation: Protection from Evil and Good, a 1st level spell that, among other things, makes the target immune to being charmed by abberations. This spell lasts 10 minutes and requires concentration, and it is a wizard spell as well as a cleric and paladin spell, so not only can your wizard NPC have the spell, the party healer can probably prepare it given advance warning of what is to come. The 10-minute time limit is long enough to have a significant conversation, but also short enough to impose some significant time pressure, and the requirement for concentration gives the aboleth the possibility of breaking the caster's concentration in order to get a chance at enslaving them, so if the players use this solution, you as the DM have plenty of opportunity to create tension during the encounter.

The downside of all of these spells, however, is that they can only protect 1 creature each, which is fine for your wizard NPC but not so great for warding the entire party.

The wizard's best defense is knowledge

Assuming the wizard's research has effectively given him complete knowledge of the aboleth's abilities, there are 2 very straightforward ways to defend against the aboleth's enslavement:

Enslave (3/Day). The aboleth targets one creature it can see within 30 feet of it.

In order to use this ability, the target must be visible to the aboleth, and it must be within 30 feet. So, as long as the wizard remains invisible or outside the range of this ability, the aboleth will be unable to even attempt to enslave him. As for how to accomplish this in practice, aboleths are quite mobile in water but only have a speed of 10 feet on land, so the wizard should not come within 40 feet of any water (10 ft movement + 30 ft range). If the aboleth has any sense, there will be no such safe point anywhere within its lair, so most likely this will mean communicating from a safe distance outside the lair, perhaps via the Message spell, which has a range of 120 feet, or perhaps a familiar carrying notes back and forth. (After any communication session, the familiar should of course be considered compromised and the wizard should dismiss and re-summon them.)

Alternatively, if especially brave, the wizard can cast Invisibility on himself and enter the aboleth's lair. The aboleth has a +10 perception modifier, so the wizard will probably not go undetected, but since the aboleth does not have truesight or any other ability to see invisible creatures, it will be unable to target the invisible wizard with its enslavement. Of course, the wizard must still remain at least 20 feet from any pools of water, or else the aboleth will be able to either attack him (10 ft land speed + 10 ft reach) or use its grasping tide lair action to pull him into the water (and then attack him). It is imperative to avoid any possibility of attack, since this has a chance to break the wizard's concentration on Invisibility.

Of course, any spell or ability that allows long-distance communication would be ideal. This includes spells like Sending and Dream. Another option for long-distance communication with an aboleth specifically would be to capture and imprison one of the aboleth's thralls, because the aboleth has a bidirectional telepathic link with its thralls over unlimited distance. Note that the thrall should be subdued without dealing damage to them, since they get a saving throw each time they take damage. The Sleep spell will likely be useful for this purpose. If the aboleth is amenable to working with the wizard, it can use the captured thrall as a messenger. As the DM, it is of course your job to come up with a situation where the aboleth would be willing to entertain this idea.

Knowledge is shareable with the party

You stated that ideally the wizard's means of defending against the aboleth's enslavement should be usable by the PCs. Fortunately, the knowledge of how to stay out of range of the effect is something that the wizard can share with the PCs, or something the PCs could discover by reading the wizard's notes. Usually PCs facing an aboleth for the first time don't know the precise limitations of its abilities, so giving this information to the players can give them a significant tactical advantage. And unlike many spells and items, this information benefits all the PCs. Of course, the wizard (or his notes) notes should also clearly indicate that the aboleth's enslavement is a charm effect, because the (non-wizard) PCs will likely have good ways of negating such effects.

Answer 2

Mind Blank

Mind Blank grants immunity to the charmed condition and so would protect the wizard from the aboleth's powers. Unfortunately it is a level 8 spell so, even though it is on the Wizard spell list, it would likely make your NPC too powerful.

Fortunately there is another way to gain the effects of the spell from Curse of Strahd:

There are a series of tombs containing dark powers that can grant gifts/curses to those who open them and succeed on a CHA save. One such power is The Dark Gift of Savnok the Inscrutable which reads (CoS, 192):

Savnok's gift is the power to shield the mind. This dark gift takes the form of a mind blank spell cast on the beneficiary. The spell has an extended duration of 1 year, after which the dark gift vanishes. The beneficiary's eyes melt away upon receiving this dark gift, leaving empty sockets that can still see.

This would protect your Wizard for 1 year assuming they found a way to contact Savnok, without getting trapped in Barovia, and successfully saved.

You could also just give the wizard a magic item that allows Mind Blank to be cast once per day.

Alternatively, if you are not set on the NPC being a wizard specifically, a Warlock of the Archfey gets immunity to the Charmed condition at level 10. If you have them take Book of Ancient Secrets this would still work with the Warlock exchanging aid for knowledge and power.

Answer 3

Tossing this out there as a frame challenge maybe more suitable for Worldbuilding.SE :) .. this popped in my head as potentially offering some fun role-playing opportunities for the party.

Suppose the wizard has no idea he’s already been enslaved?

An overconfident wizard, underestimating the cunning and power of the aboleth, has become so thoroughly charmed that he thinks he’s succeeded in fending it off when in fact it’s just the aboleth allowing him to think that. But there’s the faintest sense in the wizard’s mind that something’s ... off ...

The party could defeat the wizard and pore through his notes, but it could also maybe come to realize he’s been enslaved, fan that flame, and help the wizard break the charm. Then he would willfully give them notes and more as retribution against the aboleth for its deceit.

Answer 4

Building of off Ryan C. Thompson's Idea with "Protection from Evil and Good", I'd propose homebrewing a magic item

You're the DM, just do it. The "official" List of Magic items is merely a suggestion and there's a reason why every module released includes at least a few original ones. Now, one usually dislikes homebrewing magic items because of the (reasonable) fear of messing up. However, that's why we'll weaken the effect a lot (so feel free to buff it up again as you see fit.

The base idea is a ring that bestows the spell Protection from evil and good onto the (attuned) wearer. We could leave it here and be done with it already, an item granting a lvl 1 Spell to its wearer permanently isn't that bad at level 5-6 and reasonable to have for a BBEG of that power.

However, that item is a LOT more powerful than we technically need it to be, so any number of nerfs could be applied: (pick and remove these powers from the item as you want, the more you remove, the more mundane it becomes of course)

1.: The original spell affects the following creatures:

protected against certain types of creatures: aberrations, celestials, elementals, fey, fiends, and undead.

That is a long list. To keep it thematically you could take just "evil" creatures (removing elementals, celestials and maybe fey) from the list, or just make it obvious and be relevant to aberrations only, nothing else.

2.: The spell originally does a LOT more against these creatures

Creatures of those types have disadvantage on attack rolls against the target. The target also can't be charmed, frightened, or possessed by them.

However, we only need the immunity to charms from those creatures. Anything else is completely optional and can be removed.

If the target is already charmed, frightened, or possessed by such a creature, the target has advantage on any new saving throw against the relevant effect.

Maybe if the (new) wearer is alreay affected, this ring doesn't do anything but instead LOOSES it's magic / becomes corrupted (aka any wearer is directly under the charm instead), that majorly weakens the power further as any of the aboleth's minions can directly revert the power of the ring with a mere sleigh of hand check in a crowded bar.

Why even go of of a spell if we ignore/change most of it anyway? Firstly because it gave me the inspiration but more importantly: Because that means that the effect already exists in the official D&D Rules. And it helps to gauge the power potential: at worst it's a permanent lvl1 Spell on an item, which I think means it's "uncommon" (as valuable as the rarity rating system is anyway) at worst [For comparison, the "Hat of Disguise" from the DMG allows the wearer to cast the lvl1 Spell "disguise self" at will (aka also almost permanently on)], BUT we then further massively nerf the effects of that spell.

On the in-game lore (Especially if you tailor the ring to be as weak as possible) It will be blatantly obvious that this is the ring against the aboleth, kinda cliche so, even. But that is not a problem. Wizards know about the dangers of aboleths and want to be protected.

Maybe your Wizard randomly found the ring and only then wanted to include the aboleth in his plans (given that the ring allows him to gain an even footing against this very powerful potential minion),

OR if you completely weakened the ring, it's reasonably possible for this magic item to be crafted by almost any magic user. RAW magic item crafting is crap, but the wizards belongings could contain the instructions with maybe a enough weird rare Resource to craft one for each in the party. Aboleths are so rare that you don't need to explain why these rings aren't ubiquitous in the world.

Answer 5

Anything which grants immunity to the charmed condition

The aboleth's enslave ability charms its target, so targets immune to being charmed are immune to being enslaved.

This question tells us there are only two magic items which grant this immunity:

• Greater Silver Sword
• Staff of the Forgotten One

Of course you could always invent your own, but note that it's a high-tier passive ability and your players will likely want to take the item for themselves.

Other ideas

• If you're wizard is an elf, he'll have advantage on the save (elves have advantage on all charm-saves)
• If you're wizard is a creature immune to being charmed, he'll be immune to enslavement. Not sure if any of those creatures fit the bill though, they're generally constructs and less intelligent undead.