Last Updated: February 6, 2023
The Alchemist’s subclasses (Research Fields) choose a specific type of alchemical item and make you an expert with that type of item. This allows you to create those items more efficiently (sometimes entirely for free) using Advanced Alchemy and Quick Alchemy, so expect to spend a lot of time using whatever favorite items you picked.
All of the subclasses work roughly the same ways. At level 1, you’ll generally get some “signature items” which you’re really good at making using Advanced Alchemy. As you gain levels, you’ll get the ability to create a few items for free using Quick Alchemy without spending your precious Infused Reagents. You’ll also get some specific features which improve the functionality of your favored type of items, and it’s these features which largely define the subclasses.
Because each subclass is tied to a specific type of alchemical item, the availability of those items is central to the subclass. Make sure that you have access to materials from the Core Rulebook, the Advanced Player’s Guide, and Treasure Vault, as those three source books contain the bulk of the items that you’ll care about.
Table of Contents
RPGBOT uses the color coding scheme which has become common among Pathfinder build handbooks.
- : Bad, useless options, or options which are extremely situational. Nearly never useful.
- : OK options, or useful options that only apply in rare circumstances. Useful sometimes.
- : Good options. Useful often.
- : Fantastic options, often essential to the function of your character. Useful very frequently.
The Bomber is easily the simplest variety of alchemist to play. At their simplest, the Bomber is a Striker. But as you accumulate feats you’ll add a bit of Blaster and Controller, so your capabilities expand as you become more proficient and comfortable with your character.
If you’re not a Bomber, you’re not using alchemical bombs to their full potential. The biggest drawback to bombs is their disposable nature, which means that they become expensive quickly, which the Alchemist neatly solves with their Alchemy feature. That immediately means that you don’t need weapon options beyond bombs (except for extremely long range, which can be addressed using a Bomb Launcher from Guns and Gears), allowing you to focus nearly all of your attention on making your bombs terrifying.
Strongly consider buying a Bomb Coagulator Alembic (see Treasure Vault). A few bombs that deal a bunch of persistent damage will make a big difference in encounters against small numbers of powerful foes. Calculated Splash does not affect the Bomb Coagulator Alembic because the feat’s effect takes place when you throw the bomb, but don’t let that stop you.
- : You get two bombs added to your Formula Book for free, and those are your “signature items”, which you can make more of using your Infused Reagents. Make sure to diversify your options so that you won’t be stopped by damage resistances, but also pick bombs that you know you’ll use every day. Be sure to upgrade these as often as you can. The bombs you create at the beginning of the day using Advanced Alchemy are often your go-to option in combat. Because these bombs can be up to your level, they’ll be more effective than what you’ll eventually be able to create with Perpetual Infusions.
- : You’re going to use a lot of bombs most days, so getting extra for free is a great way to stretch your resources.
- : Lesser bombs are basically your cantrips: easily reusable, but unimpressive damage (though feats like Calculated Splash and Expanded Splash certainly improve them). You only get to pick two types of bombs which you can do this with, so pick two which you can use a lot. I recommend either acid flask or alchemist’s fire for simple, reliable damage and something with a good debuff like skunk bomb.
- : A significant increase in your damage output from bombs created for free, often doubling their damage and adding a +1 item bonus to attacks. At this level you can start crafting Greater bombs using Advanced Alchemy, but they’re limited by your number of Infused Reagents. If you don’t need the extra damage, your free option is now massively more dangerous.
- : Somewhat underwhelming compared to other research fields, but more splash area means more splash damage. And if you’re raining cheap bombs over an area with Calculated Splash and Expanded Splash, you’re dealing at least 5 splash damage to everything in a 15-foot radius burst even if you miss. Do that three times a round with permanent lesser bombs via Quick Bomber (laughably inexpensive at this level), and you’re doing a sizeable amount of damage at nearly no effort or cost, plus possibly applying effects like clouds of smoke, speed penalties, persistent damage, etc.
- : Even more damage, bigger debuffs, and item bonuses to attack rolls. Greater bombs typically offer a +2 item bonus to attacks and deal roughly three times as much as lesser bombs.
So the party asked you to play a Healer and you stubbornly refuse to play a spellcaster. Sure, you could limp along with the Medicine skill, but no amount of skill in Medicicine can match the stunning effectiveness of alchemical items’ restorative capabilities. Between available items and class feats, the Alchemist can remove nearly any status condition, as well as providing bottomless healing via Perpetual Infusions.
Unfortunately, the Chirurgeon struggles to do anything proactively. Healing elixirs are great for healing and removing status conditions, but nothing about the subclass supports overcoming challenges which your party will face. Healing elixirs can provide some defensive buffs, but otherwise the subclass is entirely reactive. You’ll need to resort to core class features and class feats to make options like bombs viable.
The Chirurgeon has seen some crucial errata. When the Core Rulebook released, I described the Chirurgeon as “a vending machine that only sold off-brand tonic water”, which still feels accurate considering that the the only thing which the Chirurgeon did well at the time was produce antitoxins and antiplagues. Paizo has wizely updated the subclass to be much more versatile, and it’s now a capable alchemical healer.
- elixir with the Healing Trait as a signature item, allowing you to create them in batches of three via Advanced Alchemy. Load up on elixirs of life at the beginning of the day and pass them out to your allies. : Unlike other alchemists, the Chirurgeon doesn’t have “signature items”; you effectively have every
- : A significant improvement to the efficiency of your best healing items, but most of your options are only situationally useful, so they’re best left for Quick Alchemy. Expect to load up on Elixirs of Life and other non-elixir items like bombs.
Note that if you use Perpetual Infusions to restore hit points, the recipient has a 10-minute cooldown. This is explicitly to prevent abuse outside of combat.
: You’re basically
obligated to choose Elixir of Life because it restores hit points, so your
second choice comes down to Addition Suppressent, Antiplague, Antitoxin, and
Vaccines, which are all only situationally useful. Fortunately, Perpetual
Potency and Perpetual Perfection will have more options.
- : Several interesting options sneak in under the level 6 cap. Contagion Metabolizer is great for the Chirurgeon and since it uses your stats, it doesn’t matter if you only ever have the level 5 version. Soothing Tonic is great to hand out right before a fight starts so that your allies can start combat with some Fast Healing to protect them from both persistent bleed and from dropping to 0 hp.
This does also apply to elixirs of life created with Perpetual Infusiions, but don’t forget asbout the 10-minute cooldown.
: At this level
you can craft a Greater Elixir of Life and heal a guaranteed 92 hit points.
In a pinch that’s really good, but in-combat healing should be a rare
fallback for when things are going badly. Still, 92 hit points is much
better than most in-combat healing, so it may actually be worth the Action
cost. Of course, this has the same cost as making three elixirs, so you’re
giving up 50% of your potential healing on average in exchange for speed, so
you don’t want to do this all the time.
- : No new options, but Elixir of Life and Soothing Tonic remain good choices.
Mutagenists are conceptually cool: Drink some stuff, and mutate yourself to adjust your capabilities. Usually this means using Bestial Mutagen to turn yourself into a melee Striker. You can get pretty durable by combining various mutagens and elixirs, but you’ll never quite be a Defender without a Reaction option like Attack of Opportunity.
Unfortunately, you’re not significantly better at using mutagens than any other alchemist until you get Greater Field Discovery at 13th level so that you can combine two mutagens at once. However, you can make good use of mutagens to buff your allies, especially once you have Perpetual Infusions and can pass out low-level mutagens like candy.
The available class feats which support the Mutagenist assume that you’re stuck with the combat mutagens available in the Core Rulebook: Bestial Mutagen and Juggernaut Mutagen. But over PF2’s lifetime, we’ve seen a number of additional mutagen and elixir options which are often more effective than Bestial and Juggernaut.
The way mutagens are designed further hampers you: the only mutagens that are universally useful in combat (Bestial and Juggernaut) aren’t very good unless you invest class feats to improve them, so you’re locked into several feats if you just want to meet a bare minimum amount of effectiveness. And even then, you’ll need expensive magic handwraps to apply runes to your unarmed strikes.
As you gain levels, it’s absolutely essential that you acquire a Collar of the Shifting Spider. Triggering a mutagen as a Free Action when initiative is rolled saves you at least one Action on the first turn of combat (possibly 2 since you need to Interact to pull the mutagen out of your pocket or to use Quick Alchemy to create one). Mutagenic Flashback helps, especially at low levels, but it’s only once per day.
If you’re working from the printed Core Rulebook, note that the Alchemist got a lot of errata to support the Mutagenist specifically because at release it was an unplayable mess. Medium armor proficiency and Mutagenic Flashback have done a lot to help the Mutagenist.
- : An emergency option for when you’re caught unawares or when you’re out of your best mutagens. It only functions once per day, so if you use it, strongly consider ending the day and getting some rest.
- : You get two mutagens added to your Formula Book for free, and those are your “signature items”, which you can make more of using your Infused Reagents. Bestial Mutagen and Juggernaut Mutagen are good go-to options at level 1. Create a big batch of each during your Daily Preparations, and when those start running short, consider calling it a day.
- : You get the unique option of crafting any three different mutagens rather than 2 or 3 of the same item like other alchemists. Be sure to bring a few different types so that you’re ready for anything.
Combined with the Revivifying Mutagen feat, this means that you can repeatedly create a free mutagen, consume it, then end it to heal.
: Pick your favorite
go-to mutagen, and make sure that you and your allies always have it
running. While this can mean having your favorite mutagen running at all
times, remember that most 1st-level mutagens won’t be especially effective
in combat, so you still need to use some Infused Reagents to make the
mutagens that you’re going to use in a fight. Instead, plan to share these
with your allies.
- : Linear improvement to your favorite mutagens, but 3rd-level mutagens on an 11th-level character aren’t much help. Plan to use them on your allies instead.
- : Combine Bestial and Juggernaut and wade into melee like a horrifying mutated wrecking ball. This is why you play a Mutagenist for mutagen builds rather than any other option. You can do this with Combine Elixirs, but it’s not quite as effective. Keep in mind that if you add more mutagens you’ll keep the benefits of two but accumulate the drawbacks of all of them. Ending your mutagens intentionally with Revivifying Mutagen allows you to reset.
- : Another linear increase in effectiveness, but the level cap is still far, far behind your actual level. Plan to use these free mutagens to buff your allies and use Persistent Mutagen and Greater Field Discovery to keep your two favorite combat mutagens running on yourself.
Poisons in Pathfinder 2e are extremely effective, but they’re also complicated, and like many consumable items they’re limited by cost, a fixed save DC, and the action economy around using them. The Toxicologist addresses all of those issues, making poisons a much more accessible combat option.
The Toxicologist Research Field allows you to apply poisons to weapons in one Action instead of the usual two, though you still need to spend one Action to draw the poison or create it with Quick Alchemy applying it. This action cost can be greatly mitigated by using an Injection Reservoir (see Treasure Vault) and/or by taking Rogue Dedication archetype feats to get Poison Weapon.
While they’re few in number, don’t overlook inhaled poisons. You can scatter them into the air in a 10-foot cube as an Action, turning that poison into a small AOE without relying on the Alchemist’s terrible attack proficiency progression. Similarly, contact poisons can be applied directly to a single creature as an Action, which requires them to immediately save against the poison without adding a Strike to the mix, but they also typically have an onset period which makes them largely useless in combat.
As a Toxicologist, your best asset is your allies. Every weapon in your party is a vehicle to deliver injury poisons, and you are at your most effective when you’re delivering as many poisons as possible as quickly as possible. To achieve that goal, you need to share your poisons with your party and trust that they’ll end up in the right place. Choosing an array of go-to poisons to apply to your party’s weapons is a great investment of real-world time, and going into every encounter with your allies’ weapons poisoned will tilt many encounters in your party’s favor.
Despite all the benefits of poisons, be aware of its limitations. Many enemies are immune to poison (constructs, undead, etc.), so you’ll need other options to handle those foes like bombs or conventional weapons. Poison can also be difficult to apply in combat, and if you’re using a weapon that needs to be loaded like a crossbow you may have turns where you don’t do anything except get ready to do something on your next turn. Managing your actions will be especially challenging in combat, so going into combat with poisons ready to go is essential. You need to have a big impact early in combat in case you find yourself struggling as combat drags on.
The two poisons you pick also become your “Signature Items” so you can create more of them using your Infused Reagents. Pick some easy go-to poisons which will be consistently useful in most combat encounters (Giant Centipede Venom is great at level 1), and plan to upgrade every level so that your signature poisons are as good as they can possibly be.
: Increasing the save DC of
poisons makes low-level poisons viable at much higher level, opening up a
much broader array of poison options than just whatever is the highest level
available to you (though that is often still your best choice). Reducing the
Action cost from 2 to 1 also means that you can more easily apply poisons in
combat, allowing you to quickly employ the right poison for the situation.
- : Much like bombs, poisons are a single-use item that you may burn through quickly in combat. Getting 50% more for free each day will stretch your limited resources considerably, allowing you to more easily rely on your best options. Plan to go into every combat with poisons applied to every weapon in the party.
When selecting poisons for Perpetual Infusions, be cautious about poisons which rely on damage and poisons with an onset time. Powerful Alchemy raises the save DC for these poisons, but the damage of low-level poisons will gradually shrink in effectiveness until you get the next upgrade to your Perpetual Infusion items at levels 11 and 17. However, debuffs will remain perpetually useful throughout your career. Tragically, the only 1st-level injury poisons are Spear Frog Poison and Giant Centipede Venom, so you don’t really get to choose.
You could more easily use this with inhaled poisons, but there are only two qualifying poisons as of this writing (False Flayleaf, Yellow Musk Vial), and they’re not useful consistently enough to justify picking them for Perpetual Infusions. Of course, a Lab Assistant familiar could run around dropping clouds of Yellow Musk Vial and make a huge impact.
It’s not clear to me if poison applied to weapons/objects or thrown into the air persists past the beginning of your next turn. If it doesn’t, this is abysmally hard to use. If it does, you can freely poison every weapon and piece of ammunition in your party after every encounter. The best answer I’ve found comes from the Infused property which the Alchemist’s Alchemy feature applies: “Any nonpermanent effects from your infused alchemical items, with the exception of afflictions such as slow-acting poisons, end when you make your daily preparations again.” I think this means that once your poison is “used” (applied to a weapon, poured into a drink, thrown into the air, etc.) it remains functional until your next daily preparations. This seems extremely powerful, especially if you poison a big pile of arrows, but I haven’t been able to find official rules answers on the subject.
: Quick Alchemy is
hard to use with contact/injury poisons in combat because you need to create
the poison as an Action, apply it to your weapon as an Action, and then
ideally hit something with it using your remaining Action.
- : Increasing the level of the poisons is great. For easy go-to options, Lethargy Poison (imposes Slowed, but has the Incapacitation trait so don’t use it against powerful foes) and Hunting Spider Venom (imposes both Flat-Footed and Clumsy) are great go-to choices.
- : The ability to combine two poisons is spectacular, but since this can’t be used on ammunition you need to put this on a melee weapon. Melee is a hard place for the Toxicologist due to the action economy challenges of using poisons, but you can use this outside of combat to set your party up with poisons that will give your party an advantage early in combat.
- : Again: better poisons are great. By this level, there are numerous contact and inhaled poisons, so it’s easy to look beyond injury poisons. Blightburn Resin deals a mountain of poison damage as a contact poison, so your dismal attack bonus no longer matters. If you can get the formula for Azure Lilly Pollen (it’s Rare), it’s a decent inhaled option.