I was thinking of introducing an NPC Witcher into my world.  As an example, how would you build a Witcher, from the Netflix Series of the same name, in D&D 5e

... at 5th level

... at 8th level

... at 12th level

... at 16th level?

Of course the Witcher has to be a multi-class, but what mix?  And assuming the character in the show is about twelfth level, what would their stats be when they started to make them a Witcher?

I hate to sound dismissive... but to me it's just a straight Monster Slayer Ranger.

You may want to check out the Order of the Mutant blood hunter, as well.  I don't play the games, read the books, or watch the shows...but everyone I know who does tells me the Order of the Mutant subclass for Blunters is basically just Witcher.  Like, barely even disguised.

Someone on reddit made Geralt purely as a warlock

If you’re comfortable with homebrew I created a Witcher Subclass for fighter and all of the signs, including a couple of the signs only found in the extended universe (like the graphic novels):

(https://ddb.ac/characters/62333718/oQvq4M)

If you’re interested PM me with a link to a private campaign for two and I’ll gladly hook you up.

An Eldritch Knight Fighter covers most of what a person would want…minor casting; heavy on martial prowess.

A Monster Hunter Ranger is another good one…their 3rd Level ability even lets them identify a monster’s weaknesses & vulnerabilities, just like a Witcher.

A Vengeance Paladin has smites, a Channel Divinity that lets them lock-down a single target, and the ability to move gracefully through the battlefield unimpeded…sort of like a Witcher.

”Aard” is your Thunderous Smite…”Igni” is your Searing Smite…etc.

This is an older post but since I recently built a Gerald inspired character for a one-shot, I did want to comment and go over my thoughts. 

First the only real options for base class were ranger and fighter. I still wish there was a magic-less ranger. That with the monster slayer subclass would be perfect. The real issue is that there are 3 primary versions of Geralt: the books, the games and the series. So first you have to decide which Geralt you are playing. Then you have to decide on how important the overall theme is verse optimization. Geralt can be thematically created for all 3 versions pretty easily, but they aren't too effective especially in combat, you wont have any primary ability score over 16 until late game. Going to optimization and overall effectivity, things are also pretty easy but you definitely lose the "Witcher" vibe to an extent. I am gonna go with the book Geralt since I know the books better than the games. 

Book Gerald thematically built would be a swashbuckler rogue 16, eldritch knight 4. Geralt would have the multi attacks of the fighter, dex based attacks plus the skill monkey ability of the rogue and sneak attack for a but extra damage. Also with EK you get access to enough magic to replicate the signs he does know. overall with the right skills the build works very well. the issues come when you need Dex, Int, and Con all very high to make the build go off. You can get away without Int if you pick the right spells and use them right, but they cant be really offensive since your spell save dc and spell attack rolls will be low. You could compensate and take a lower score in Con and pad it out with touch or resilience in con depending on how true dm wants to work the Witcher potions/mutagens. But also for RP, you will need a high Int for checks. Cha is an easy dump here and Str is the next lowest then Wis, and a tight between Int, Con and your highest being Dex. So like I said, it's not optimizable like this. 

Now going book Geralt optimized for dnd overall would be a Ranger monster slayer. You gain a lot of the Geralt has but you pushed to use magic still as a ranger since the class revolved heavily around hunter mark. Alot of the spells are very easily flavored as signs, though they are higher level spells like gust of wind. But this is a much more effective build but it does lose that Geralt and Witcher vibe alot. Now that can be made up with RP. 

Also something to ask yourself, when you pick a version and build type, is do you want to play and Geralt/Witcher inspired character OR are you going to Play Geralt? If you are going for inspired then, in my case with the Book Geralt, go with the Ranger. If you want to go with a thematic playing of Geralt, go with the Rogue/Fighter multi class.

Quote from Jessebruffett >>

Book Gerald thematically built would be a swashbuckler rogue 16, eldritch knight 4. Geralt would have the multi attacks of the fighter

At level 4?

I'd go rogue until level 4, then segue into EK for its 4 levels then back to rogue. At level 4 or with one of your origin feats if you use 2024 rules or V-human in 2014, take magic initiate to get a few spells as signs for lower level play IF signs are that important to you. 

Quote from Jessebruffett >>

I'd go rogue until level 4, then segue into EK for its 4 levels then back to rogue. At level 4 or with one of your origin feats if you use 2024 rules or V-human in 2014, take magic initiate to get a few spells as signs for lower level play IF signs are that important to you. 

You misunderstand. You said a swashbuckler 16/EK 4 would have "the multi attacks of the fighter", but that build only gets one attack per round. Fighters don't get Extra Attack until level 5

You're right, my bad. EK 5 and Rogue 15 is what I meant. 

Matt Mercer's home-brew Bloodhunter Ranger subclass is a pretty good option.

It really is pretty close, but I try not to use 3rd party content. Plus for the Witcher, you do need some magic. Book Geralt did you igni alot for fires and touches, aard was used a few times, etc. So you'd need to take magic initiate and/or multclass. Ranger wouldn't be my first pick though, signs are basically cantrips and they don't upgrade in the books like they do in the games, so mainline spellcasting isn't a good match. Plus blood hunters secondary ability is charisma, so the MC should need to be sorcerer, not at all thematic, or warlock, also not thematic. It would be really nice if Matt Mercer updates Bloodhunter for the 2024 rules but I honestly doubt he will. I think they are don't with WotC products after Campaign 3 is over. 

Im waiting and hoping for a few more subclasses in some of the other books later his year before I make another build of him for the 2024 rules. 

Idea: it wouldn't be very strong, but for 2024 then elemental monk plus hunter ranger works nicely, because elemental monk gives you igni and such, and ranger because of colossus slayer.

Quote from IamSposta >>

If you’re comfortable with homebrew I created a Witcher Subclass for fighter and all of the signs, including a couple of the signs only found in the extended universe (like the graphic novels):

(https://ddb.ac/characters/62333718/oQvq4M)

If you’re interested PM me with a link to a private campaign for two and I’ll gladly hook you up.

 I had the pleasure of reviewing this and if Sposta is still around to give it, anyone interested in a Witcher homebrew would love it. I am not a hardcore Witcher fan but I have played the games and watched most of the show. It feels about as close as can be.

Ranger, Blood Hunter or even Paladin or Cleric fit (if you focus on their hunting down undead/super natural crap that goes bump in the night). 

I checked it out and it's not bad. Again, it depends of which iteration of Geralt you're looking to build. Book Geralt barely uses signs, aard and quen are the only signs he used in combat. And quen was only used once in combat against the striga. The others are all really only for utility. Signs are also really bound to his witcher elixirs. He can do them without it but it's much more taxing. Also in the books these produce set effects, they don't get stronger with time/age. They are the most basic form of magic in the world.

I think IamSposta for the class right for a HB, but I think giving scaling spells for it is a mistake. If nothing else add a feature for the signs and allow the get all 4 as part of the feature. Signs should only be cantrips. My picks are Aard: gust, igni: product flame, Quen: Resistance or blade ward and Axii: friends. Yrden is only mentioned once in the books and it is a magical seal like arcane lock so it doesnt really work and as its said to be rare and never actually seen used id omit it. IF you feel the need to add a 5th one for balance id do something to add the new true strike since it's actually worth using now. Book Witchers are much more about potions, and just sticking with their swords.

The best way to do a HB subclass would be to look at some of the balance of the mutagen's and move some of that over to a fighter subclass. If you play 2014 rules only and signs are super important to your build talk to your DM about adding magic initiate or a custom feat that gives those cantrips as witcher signs. Im not a fan of that option because I don't see the Blood Hunter being updated for 2024 rules. Also the Blood Hunter base class features don't work thematically. So with that I would suggest creating a custom Fighter subclass for it that gives the 4 cantrips and reworks the Order of the Mutant subclass to better fit into Fighter. 

TBH I may give this one a shot. If I do, I'll post it here and in the Homebrew forum for critics, suggestions and reviews.