Need feedback on a Fighter Subclass, please!

[Darkstar_Child]

Hey all! I am new here, but I am working on a campaign setting based on a Library Plane. Here is an idea for a fighter subclass that would live there. Tell me what you think!

Librarian Delver (Fighter Variant)

Hit Points
Hit Dice: 1d10 per Guide Level
Hit Points at 1st Level: 10 + your Constitution modifier
Hit Points at Higher Levels: 1d10 (or 6) + your Constitution modifier per Guide level after 1st

Starting Proficiencies
You are proficient with the following items, in addition to any proficiencies provided by your race or background.

Armor: All Armor
Weapons: Simple and Marshal
Tools: None
Skills: Acrobatics and Choose two from Athletics,History, Insight, Investigation, Perception, and Survival

Starting Equipment
You start with the following items, plus anything provided by your background.

• (a) Chain Mail or (b) Leather Armor and a Hand Crossbow with 20 Bolts
• (a) Two Shortswords or (b) a Shortsword and a Whip
• (a) a Diplomat’s Pack or (b) an Explorer's Pack
• A Large Scroll Case, a Library Acquisitions Guild Pin, Grappling Hook, Hammer and 10 Pitons

Librarian Delver Archetype:
The Librarian Delver is a seeker of knowledge, magic items and all around helper. They are also amazing guides for those who first come to the Great Library. As such, the Delver is very much influenced by their environment: colossal bookshelves, long treks with uncertain outcomes and lots of climbing a repelling. Most Delvers, or ‘Dellys’, find themselves constantly moving, never really having a place to call home, and very rich by the end of their journeys.
The Delver is also tasked by other Librarians to find magical items and lost tomes within the Great Library. They often get these jobs from the Library Acquisitions Guild located in the Citadel of Circulation. Whether to deliver a message,fight off a horde of Page Ravens, or just find a lost book, jobs can be taken up here by any guild member. Although membership is not required to be a Delver, the Guild is always looking for new victi… I mean members.

Aerial Combatant
Starting at 3rd Level, you have gained enough skill to be more dangerous while in the air, hanging from a rope, or when simply above another person. The Stacks have trained you well! You gain advantage on climb checks, checks made with rope, and on all attack rolls made on targets that are more than five feet below you.

Researcher at Heart
At 7th level, finding items and getting to them quickly becomes second nature to you. You now have one Adventure Trick slot per a short rest. An Adventure Trick slot can be used to cast a spell from the matching Adventure Trick spell table. Each Trick only costs 1 slot, and it can only be used on yourself or an item. They are all cast at their base levels.

Adventure Trick Level and Spells
7th Level, 1 Slot: Jump, Longstrider and Locate Object
10th Level, 2 Slots: Misty Step, Detect Magic, and Feather Fall
15th Level, 3 Slots: Gaseous Form, and Haste
18th Level, 4 Slots: Leomond’s Secret Chest, and Fly

Stacks-Fighter
Through grit and determination, you have learned how to counter attacks very effectively with only the lightest of touches so as not to disturb the books around you.. At level 10, when an opponent misses on a Melee Attack Roll, you can take your reaction to make a Melee Attack if the target is within 5 feet of you if you are using a Finesse Weapon.

You move like they do!
Nimble, lithe, agile. These are all words that describe the way you fight! When you get to level 15, you have an additional 15 feet of movement, and gain the Acrobat feat.

Herald of the Stacks
Nothing about being out in the Stacks surprises anymore. Book Golems, Page Ravens or even the Curators don’t make you nervous. That being said, at level 18, you gain advantage on attacks on any monster that would be considered to have the subtype of Extraplanar on the Material Plane.

Delver Personality
Librarian Delvers are confidant, smart and outgoing. They have little regard for danger, and see it as more of challenge to be overcome than a threat to humanoid life. Having a love for all things shiny and rare, Delvers are collectors of items, knowledge and new experiences, even to their detriment sometimes. Often serving as guides for those new to the Great Library, they often charge in these oddities. Treasure and tomes are often required for safe passage, although some Delvers have more eclectic tastes, asking for strange things like ‘the color of your eyes’ or ‘all your memories of your first crush’. Although it is not known if they can truly get such things, this definitely adds an air of mystery and danger to the Delvers.

[Cynthaer]

General Thoughts

First, this is an extremely specific concept to build an entire subclass around. This isn't necessarily a bad thing, but it's worth keeping in mind.

Second, this doesn't actually feel like a Fighter subclass to me—it feels like a Rogue subclass.

Let's look at the features to see why:

Level 3: Aerial Combatant—advantage on climbing and rope use ability checks, advantage on attacks from above
Level 7: Researcher at Heart—handful of mobility and detection spells
Level 10: Stacks-Fighter—reaction counter-attack, Finesse weapons only
Level 15: You move like they do!—extra move speed, +1 Dex, proficiency/expertise in Acrobatics
Level 18: Herald of the Stacks—pseudo "favored enemy" effect

There's a pretty clear theme here. A Dex-based character with high mobility, finesse weapons, and good skills. As you yourself say: "Nimble, lithe, agile. These are all words that describe the way you fight!"

It's not impossible to cram this into a Fighter chassis, but you're basically describing the defining attributes of the Rogue.

So, before taking this design any further, I think it's worth asking why we should bother to build or use this subclass when we have at least one Rogue subclass that works quite well: the Thief.

- Expertise can of course be placed in Acrobatics and Athletics (similar effect as Aerial Combatant and You move like they do!). Later on, Reliable Talent also kicks in.

- Cunning Action for Dash or Disengage gives battlefield mobility.

- Fast Hands: Instead of getting tools to find items, you get the tools to retrieve them. Note that this is much more useful in the average campaign, and therefore does a better job of communicating "obtainer of things" in my opinion.

- Second-Story Work: Effectively grants a climb speed, plus a ribbon ability to jump farther.

- Use Magic Device: Being able to use any old scroll you come across certainly feels like something a Library Delver would get, doesn't it?

With that in mind, if you want a subclass that really resonates with your concept, I think you have to answer the question: Why should this character archetype not just be a Thief Rogue?

(And if you do have an answer for that, the next question is: Why should this character archetype be a Fighter subclass instead of a Rogue subclass?)

[jiriku]

It's not clear whether you're looking to make a fighter subclass or a variant fighter class AND a new subclass. I would recommend that you stick with the subclass only -- the concept of "combat-ready explorer and magic item hunter who specializes in library dungeons" is not large enough to require a new class. With homebrew, always go as small as you can, packaging your concept in the smallest design space that will fit it.

In fact, let's get down to brass tacks -- the flavor here feels more like a background than a subclass, since it involves a specific profession and membership in a group. I think your campaign could really get some use out of a background called "Librarian Delver" that granted proficiency in Acrobatics and Investigation, with a background perk of "Member of the Library Acquisitions Guild" that granted you some guild-related perks, and a few background items like the guild pin and perhaps a map, a scroll case, and a fragment from a mysterious book. After all, why would only fighters be dungeon delvers? The flavor of the subclass you wrote makes it clear that rogues and arcane casters also bring relevant skills to the job.


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But if you are certain that you need a dungeon delver subclass, let's proceed with examining the subclass.

I suggest scrapping the class variant and sticking purely with the subclass. Grant Acrobatics at 3rd level as a bonus proficiency.

Researcher at Heart: The choice of tricks is a little weird. Not sure why you're deferring detect magic until 10th level. Given that a delver is a seeker of knowledge and magic items, I'm curious why you didn't include spells like comprehend languages, identify, or legend lore

You move like they do!: Granting the Acrobat feat is an awkward add-on. Class features should never grant feats. That's what ability score increases are for. Of the three benefits provided by the Acrobat feat, the Acrobatics skill is redundant since the character already has it, the Dex boost is redundant since a character of this level has probably already hit 20 Dexterity, and only the ability to ignore difficult terrain is relevant. I recommend that you simply grant the character the always-on ability to ignore difficult terrain without needing a die roll. This will accomplish what you wanted to accomplish here and it won't clutter up the game with excess die rolls.

[Cynthaer]

In fact, let's get down to brass tacks -- the flavor here feels more like a background than a subclass, since it involves a specific profession and membership in a group. I think your campaign could really get some use out of a background called "Librarian Delver" that granted proficiency in Acrobatics and Investigation, with a background perk of "Member of the Library Acquisitions Guild" that granted you some guild-related perks, and a few background items like the guild pin and perhaps a map, a scroll case, and a fragment from a mysterious book. After all, why would only fighters be dungeon delvers? The flavor of the subclass you wrote makes it clear that rogues and arcane casters also bring relevant skills to the job.

I actually like this quite a bit. The more I think about it, the more I feel like this is a character build that's disguised as a new subclass.

I think the concept is quite cool; it's just that the mechanics to support it are already there. Like jiriku says, create a custom background for Librarian Delver, then build your character however you like. The design you describe in the OP suggests a Thief Rogue to me (as I detailed in my own post), and you can pick your own proficiencies, expertise, and feats instead of building a subclass that forces one specific path.

In fact, here's how I would build this character concept today. (I'm choosing a Variant Human with a flavorful feat to keep things "generic", but any race works fine.)

Librarian Delver

- VHuman, Keen Mind or Linguist feat, stat boosts +1 Dex/+1 Con/+1 Int (from feat)
- Stats Str 8/Dex 16/Con 14/Int 14/Wis 14/Cha 9

Background: Librarian Delver (custom), proficiencies in History, Investigation, calligrapher's supplies + one language (or just 2 languages)

Level 1: Rogue 1, skills are Acrobatics, Perception, Slight of Hand, Stealth, Expertise in Acrobatics and Investigation
Level 2: Rogue 2
Level 3: Rogue 3, roguish archetype is Thief
Level 4: Rogue 4, ASI goes to Dex or whatever feat you like
Level 5: Wizard 1, 1-level dip for three cantrips and six spells (you could put this dip anywhere; I just stuck it after the first ASI)
- Some thematic cantrips are Light, Mage Hand, Mending, and Message
- Some thematic 1st-level spells are Comprehend Languages, Detect Magic, Feather Fall, Identify, Illusory Script, Jump, and Longstrider
Level 6: Rogue 5
Level 7: Rogue 6, Expertise in History and Perception

...and so on from there.