I'm quite the novice when it comes to the heaps of lore around DnD, but suffice to say I'm trying to create a loosely-threaded campaign that revolves around undead. That being said, I really like the concept of Hags. Given how the magic associated with Hags is, to put it politely, "weird", I was wondering if anyone knows of a reason why a Hag wouldn't be able to attempt to achieve Lich-dom?

Hags aren't mortals, so they have less reason to try and seek out undeath because it's not going to affect their lifespan.  And it's not uncommon for fey to be unable to become undead in the first place.

It doesn't seem that there are many, if any qualifications as to who can and cannot become a Lich, so I'd say yes. All you need is to have a strong magical and mental stability to ride out the transformation. Whether they'd want to or not, I can't say, but I'd assume it's possible.

If you're digging into lore, then the lore needs an answer for why a hag would become a lich.

Here's a thought: The hag didn't choose it. The hag was chosen. The question begs again as to why?
Here's another thought: Maybe a phylactery is holding the hag hostage. The question begs again as to why?
Someone who needs the hag's power but isn't powerful enough to dominate the hag is a good candidate. Then, the question doubles into why and how.

Questions, questions. That's lore for ya.

In D&D, nearly anything is possible. If you want to have a hag lich, have one. If you want to have lore about it, roll up your sleeves.

Consider that, occasionally, it's better to leave some things to conjecture.

(Don't leave the reward or finale to conjecture, though. An empty box after 3 campaigns is not a reward. Bioware found out the hard way.)

i like eric's answer. I'd say 'sure they can'...but 'why'?  I'd think they'd think its a degradation.  Why would you want to turn yourself into a monkey?

I think there are other ways to play more powerful hags, a prime example being the Sea Fury from EGtE. The Lore for these is really interesting, basically a hag in a coven of sea hags kills her sisters, and takes their power, basically becoming the alpha female, and gaining massive power. You could really do the same thing with all hags, and that creates some interesting homebrew options. But back to the OP's original question, I personally think that RAW for the way liches work, hags wouldn't be traditional liches in name, but you could have something similar that warps the hag into an undead because it seeks too much power, blah-blah-blah, etc. etc. 

Also thank you for bringing this up, I would encourage you to go ahead with it if that's what you're planning. It's a cool idea, and it's given me some cool ideas! ;)

- Gh0styy

I'm not sure about them beocming a Lich but cross a Hag Coven with a Skull Lord (from MToF) and see what your players do. The Skull Lord is born from infighting and betrayal so a Hag Coven devolving into a "civil" war and winding up bound together in the Shadowfell in some undead form could be an interesting BBEG.

I like the idea of a hag becoming a lich, and using the other members of its coven as living phylacteries. The only way to kill one is to kill them all.

IMHO, a hag doesn't need the typical reasons a mortal does, because they are immortal.  Now could one do it...maybe, but I wouldn't use the standard lich stuff either.  Hag have access to weird magic, so whatever they do, should break all the norms.  Ideas:

• Pull a soul from a soul bag, to power their spell slots.
• Form a coven from the skulls of fallen hags.  Kill a skull, pop another into its place.  Perhaps the skulls are demiliches in effect.
• Intelligent undead come to her to bargain, instead of mortals.  So a wake of strange cursed undeath things follow the hag and or pleading for release from her clutches
• strange undead minions she has crafted/grafted/adopted as part of herself (extra limbs, creating extra actions/multiattack.

Twist expectations and have fun.

They CAN; but they really don’t have to.

Hell, more often than not not, they are the ones who bargaining the secret of lichdom to amusing, foolish mortals.

Personally, I'm not convinced hags want (or need) to resort to lichdom.

To start with, they're incredibly long-lived - the Monster Manual refers to them as "virtually immortal", and mortality is typically the motivator for becoming a lich. Moreover, becoming a lich usually involves bargaining with powerful beings from the Outer Planes. Hags are known for their selfishness and independence, and even struggle to work with one another; it's hard to imagine them putting themselves under the power of another creature willingly.

That said, ancient hags and hag covens are exceptionally powerful in their own right. There's plenty of scope for them to employ necromancy and the undead, if that's the vibe you're going for in your campaign. Similarly, Night Hags already go after mortal souls - so there's plenty to play with.

Thanks all for the advice :) It is looking like I misunderstood the use of Lichdom, being the gateway to power that was locked away from those who didn't achieve the status rather than the means to pursue the quest for knowledge & power forever.

My goal was to have the Hags as an ancillary evil tangentially related to the main campaign where a mortal is trying to achieve Lichdom. I have the Hags conducting an experiment on a broken artifact (the Bone of Doresain) and was going to use it as an introduction to their own journey to investigate necromancy.

The above posts all being said, this now doesn't seem in-keeping with the lore so I may just have the Hags be fiddling with the remains of the artifact to see if they can do something weird with it, and let Hags be Hags.