Is this Sorcerer of Mirrors subclass balanced?

Question

The subclass described below is a homebrew sorcerer that focuses on divination through mirrors. It's part of a set of classes I'm designing that attempt to make divination magic more interesting for the players in D&D 5e.

I have three main concerns about it specifically, but I am also interested in general feedback about balance (this is one of the first subclasses I've tried to create, discounting deliberately unbalanced just-for-fun subclasses). I'm likely to be the person DM'ing any player with the class, so I'm not worried about DM buy-in, but I'm interested in hearing how more experienced DMs think such a player might complicate the DM's job.

What I'm wondering:

• Is this class balanced for a player, in that it specifically wouldn't leave other players feeling underpowered in the campaign?
• Is this class balanced for a PC villain, in that it would make for a fun villain who wouldn't make the game less fun for the players?
• Does the class encourage players to play in a way that is otherwise problematic? (For example, I want to avoid making a player class that is encouraged to spend more time soloing than the typical thief player.)

Thanks in advance for any feedback!

(Major credit for this class's inspiration goes to the Lady Blue from Mark Lawrence's series the Red Queen's War!)

The Mesmer

The Mesmer is a sorcerer attuned to mirrors, reflections, and the boundary between the real and the uncanny. Mesmers specialize in divination, illusion, and enchantment, and have a particular knack for casting spells using reflective surfaces. Frequently, their reflections appear to possess unusual aspects, such as always appearing to be sick or injured, not appearing at all in mirrors, or acting independently of the real mesmer. Mesmers are often sought as spies, information gatherers, and communications specialists by powerful factions.

Reflective Magic

1st-level Mesmer feature

Starting at level 1, you learn additional spells at certain levels in this class according to the Reflective Spells list, below. These spells count as sorcerer spells for you, but they do not count against your number of spells know.

Reflective Spells

• Level 1. detect magic, charm person, mirror projection (see below)
• Level 3. locate object, calm emotions
• Level 5. clairvoyance, enemies abound
• Level 7. arcane eye, dominate beast
• Level 9. scrying, mislead

Reflective Casting

When you can see an undisturbed mirror-surface within 30 feet using your non-magical sight, you may use it to cast spells from your Reflective Spells list without providing verbal, somatic, or material components. (See the mirror projection spell description, below, for more information on mirror-surfaces.)

Far Adept

6th-level Mesmer feature

Your reflection on reality has made you adept at Divination spells. When you cast the clairvoyance, arcane eye, or scrying spells using your Reflective Casting feature, the casting time is only one action, the spell grants you both remote audition and remote viewing, and you are not blinded or deafened to your own senses while remotely perceiving. Additionally, the visual and audio you receive from the spell is projected from the mirror-surface used by the Reflective Casting feature such that everyone within 30 feet of the mirror-surface can see and hear the remote location.

Far Open

When you are concentrating on a clairvoyance, arcane eye, or scrying spell that was cast using your Reflective Casting feature, you may use an action and four sorcery points to open a 2-way visual and aural window to the location of remote perception for the duration of your concentration. In order to be able to open such a window, there must be an undisturbed mirror-surface in the remote location (see the mirror projection spell description below for more information on mirror-surfaces). The window connects the remote and nearby mirror-surfaces such that other creatures within 30 feet of either surface may see and communicate through the window. If either mirror-surface is broken or disturbed, then the channel closes and the spell ends prematurely.

Far Caster

14th-level Mesmer feature

You have grown so accustomed to the nature of reflection that mirrors have become conduits for not just your mundane sight but also your inner eye. You now maintain any magical senses such as darkvision or truesight when you are remote viewing.

While you have a window open to a remote mirror-surface using your Far Open ability, you may use the remote surface to satisfy the mirror-surface requirement of your Reflective Casting ability to cast spells as if you were in the remote surface's location. Additionally, you may concentrate on two spells at the same time as long as both were cast using your Reflective Casting feature and as long as exactly one of the two spells provides remote viewing (clairvoyance, arcane eye, scrying, or mislead). If you fail a concentration check or cease concentrating on either spell then both spells end.

The mislead spell is special. When you cast mislead using this feature, the original remote viewing spell ends and you do not become invisible. Instead, your projected image in the remote mirror-surface becomes your duplicate and emerges from the remote mirror-surface.

Far Walker

18th-level Mesmer feature

When you cast the mislead spell using your Far Caster feature, you may optionally swap places with your illusory duplicate immediately after it emerges from the remote mirror-surface, and this swap is not directly perceptible to others. Additionally, whenever you are concentrating on mislead, you may cast the charm person, mirror projection, and calm emotions spells as if you were in the location of your illusory duplicate, and you may concentrate on both calm emotions and mislead (both spells end if either spell ends).

Mirror Projection (cantrip)

Casting Time: 1 action
Range: 30 feet
Components: None (this cantrip is always subtle)
Duration: 1 minute
School: Illusion

Choose 1 mirror-surface (see below) within range that you can see. You may project silent illusions into the reflection of this mirror-surface. The illusions may be of anything that you can imagine, but they must remain constrained to the mirror-surface. The illusions may appear to have depth (e.g., reflections of illusory objects may appear different from different angles). You may control only one mirror at a time using this cantrip.

At higher levels. You may simultaneously enchant 2 mirrors when you reach 5th level, 3 mirrors when you reach 11th level, and 4 mirrors when you reach 17th level.

A mirror-surface is any undisturbed non-magical reflective surface that you can see with your non-magical sight and whose surface area is at least 2 square feet (i.e., larger than a hand-mirror). Examples include unbroken plain mirrors, still pools of water, and unclouded reflective panes of glass. If you must use a magical effect such as an ability granted by an Eldritch Invocation or a spell in order to see a surface then it is not considered a valid mirror-surface. A mirror-surface that becomes disturbed (a mirror that is broken, a still pool that is struck, a glass that is clouded, silver that is tarnished) or that disappears from the caster's non-magical view immediately ceases to function as a mirror-surface.

Answer 1

This class is weak, clunky, oddly named, relies too much on the DM, and overpowered all at the same time

Lets start with the easy one:

The name

Mesmer

This brings to mind enchantment magic rather than divination magic. I know you have talked about it in comments, but when you have to justify your choice, it usually means that your choice is wrong. Nothing wrong with using whatever name you want of course, and that is the least of your issues.

The abilities

Reflective Magic

If I was comparing this to the PHB subclasses I might be tempted to say 'wow you have solved the achilles heal with the class by adding more spells known!' but actually I compare this to the new subclasses and this is quite poor.

Firstly, while in theme, a lot of the spells are pretty underwhelming. Secondly the other subclasses allow you to change the spells known from 2 of the schools of magic.

Reflective Casting

This might seem thematic, but it relies entirely on where the DM wants to place a mirrored surface. A DM has enough to think about without having to enable (or otherwise) your class abilities.

Wild magic is such a poor subclass partly because it relies far too much on the DM. Avoid this.

Far Adept

Meh. If you have time to sit and watch a situation you have time to cast the spell. This will rarely come into play.

Far Open

Interesting theme in that you can effectively communicate through a mirror, but generally either this isn't massively relevant to a campaign, or the DM gives the party some way around it, so it isn't hugely effective. Still I do quite like this and it is reasonable in power.

Your problem of overworking the DM doesn't get any easier though.

Far Caster

This is where you break the game.

Firstly, just don't mess with the concentration mechanic. It is a core feature of spellcasters, it doesn't matter the type of spells you allow with it, just don't mess with it. And especially if you consider my recommendation above to allow the spells to be changed.

And then what you have done is allow for the old scry-and-die playstyle to return, where you can just watch from a safe distance and cast spells. Thankfully your spell list is pretty poor, but enemies abound can cause all sorts of trouble while keeping you entirely safe.

Far Walker

Being able to just appear anywhere there is a reflective surface. Sounds nice, but if you can't take your party with you then this just becomes an escape mechanic or a ribbon. Way to weak for a high level feature.

The spells

Mirror Projection (cantrip)

This is just minor illusion with mirrors, I am not sure it is needed at all.

The summary

I think you have taken a theme and stuck to it, which is very good to see, but the class is a strange combination of too weak and too strong.

My advice

1. Rename the class (or change it up to be actually mesmerising)
2. Don't mess with concentration
3. Rethink your 'cast from afar' options
4. Allow for the spells to be changed
5. Remember that combat is a HUGE part of the game and you only have 1 combat effective ability (the broken one)
6. Get rid of the mirror surface thing, at least at the target end
7. Don't put any more work on the DM

Other notes

Your stated goal was to make divination interesting, and I think you are pretty wide of the mark. All you have done is tie the spells to mirrors.

Answering your questions

Q1. Is this class balanced for a player, in that it specifically wouldn't leave other players feeling underpowered in the campaign?

A1. It definitely would not leave other players feeling underpowered, but you are doing that by making the sorcerer (already a pretty weak class aside from the new subclasses) weaker. That isn't really the best way to consider balance concerns.

Q2. Is this class balanced for a PC villain, in that it would make for a fun villain who wouldn't make the game less fun for the players?

A2. Villains already get whatever magic items they need to improve the plot, an NPC with a crystal ball would do.

Q3. Does the class encourage players to play in a way that is otherwise problematic? (For example, I want to avoid making a player class that is encouraged to spend more time soloing than the typical thief player.)

A3. Yes. This encourages players to bug the DM with 'is there a reflective surface?' and 'is that reflective?'. It also doesn't really include the rest of the group while you hog the spotlight casting divination spells only to realise that when you get into combat you have wasted all your sorcery points and have no combat effective features.

Answer 2

This subclass is too weak

All of the abilities are circumstantial. There might be a campaign where you get to use these abilibites exactly never. The double-concentration might be a problem, but it is so limited as to possibly never come up. This subclass would need a very specific campaign to be able to put these abilities to use. Charm Person via a Subtle Spell equivalent is okay, but Charm Person already has drawbacks, and Sorcerers already have access to Subtle Spell. The entire skill tree is dependent on a reflective surface, which, again, you might have exactly never in some campaigns.

The extra spells are also strictly weaker than the Tasha's Sorcerers, since the Tasha's Sorcerers are allowed to change out the extra spells they receive. It is a decent feature compared to non-Tasha's Sorcerers, just becaue they are free, but these aren't really high-impact spells, mostly being circumstantial.

Mirror Projection seems worse than Minor Image, what do you do with an image in a mirror?

I do like the name.