I’ve made an abjuration-focused subclass for the sorcerer, and also applied it to make NPC statblocks of varying CRs (4th, 9th, 14th, 18th levels; CR 4, 10, 14, 17). The mirror mage not only stops unfriendly attacks and spells, but bounces them back at the aggressor. They can also thrive on illusions and enchantments, most of which involve making copies or duplicates.
Mirror Mage from Legends of Runeterra, art by Kudos Productions
You can spend sorcery points to augment some of your spells.
Shield: If casting shield causes the triggering attack to miss, you can spend a sorcery point to immediately force the attacker to repeat the attack against a creature you can see within 30 feet of you.
Mirror Image: You can spend 1 sorcery point when you mirror image. Whenever one of the spell's duplicates is hit with an attack, the attacker takes 7 (2d6) force damage.
Counterspell: If casting counterspell successfully counters the triggering spell, you can spend a sorcery point to cast the countered spell using your spell save and spell attack modifier, choosing new targets for the spell. If the spell is above 3rd level, you must spend an additional sorcery point for each spell level above 3rd.
Hallucinatory Terrain: You can spend a sorcery point to cast hallucinatory terrain using an action instead of 10 minutes.
Seeming: When you cast seeming, you can spend a sorcery point to choose up to 5 creatures disguised by the spell. Those creatures each gain temporary hit points equal to your sorcerer level.
Refract Cantrip
6th-level mirror mage feature
When you cast a cantrip that does damage to a single target, you can use a bonus action to choose a second target for the cantrip. If the secondary target takes damage from the cantrip, they take half as much damage instead.
Create Duplicates
14th-level mirror mage feature
You can use your action to create four identical duplicates of any creature you can see at empty spaces within 60 feet of you. Each duplicate has AC and hit points equal to your spell save DC and is a construct creature that disappears when reduced to 0 hit points. They have the same statistics and movement options as the target but lack all traits and unique actions of the target.
During each of your turns, you can direct the duplicates' actions using a bonus action, and they act on the same initiative immediately after your turn. Given no actions, they take the Dodge action. Each duplicate gains the following action which replaces your attack action.
Force Strike. Melee or Ranged Spell Attack: + your spell attack modifier to hit, Reach 5 ft. or Range 60 ft. Hit: Force damage equal to your Charisma modifier.
Once you use this feature, you can’t use it again until you complete a long rest.
Silverwalk
18th-level mirror mage feature
Once during each of your turns, you can spend 5 feet of movement to enter a reflective surface and exit from another reflective surface within 60 feet of that one.
NPC STATBLOCKS
Mirror Mage (Lesser)
Medium humanoid (any), any alignment
Armor Class 10 (13 With Mage Armor)
Hit Points 30 (4d8+12)
Speed 30 ft.
STR 10 (+0) DEX 11 (+0) CON 16 (+3)
INT 10 (+0) WIS 11 (+0) CHA 16 (+3)
Saving Throws Con +5, Cha +5
Skills Arcana +3, Deception +6, History +3, Perception +3
Senses passive Perception 13
Languages Any four languages
Challenge 4 (1100 XP)
Proficiency Bonus +2
Spellcasting. The mage is a 4th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 13, +5 to hit with spell attacks). The mage has the following sorcerer spells prepared:
Cantrips (At-Will): fire bolt, message, minor illusion, prestidigitation, ray of frost.
Metamagic: Distant Spell. The mage spend a sorcery point to double the range of a spell they cast if its range is 5 or more feet, or make a spell with a range of touch have a range of 30 feet instead.
Metamagic: Twinned Spell. The mage copies a spell they cast, which can only have one target, by spending Sorcery Points equal to the spell slot spent. They must choose a new target for the copy.
Metamagic: Mirror Abjuration. The mage can spend a sorcery point whenever they cast shield or mirror image for additional effects (listed in Actions and Reactions).
Bonus Actions
Refract Cantrip. When the mage casts a cantrip that does damage to a single target, they can use a bonus action to choose a second target for the cantrip. If the secondary target takes damage from the cantrip, they take half as much damage instead.
Fire Bolt (Cantrip). Ranged Spell Attack: +5, Range 120 ft., one target. Hit: 5 (1d10) fire damage.
Ray of Frost (Cantrip). Ranged Spell Attack: +5, Range 60 ft., one target. Hit: 4 (1d8) cold damage. The target’s movement speed is reduced by 10 feet until the start of the mage’s next turn.
Reflective Mirror Image (Costs a 2nd-Level Spell Slot). The mage casts mirror image and spends 1 sorcery point. Whenever one of the spell's duplicates is hit with an attack, the attacker takes 7 (2d6) force damage.
Reactions
Reflective Shield (Costs a 1st-Level Spell Slot). The mage casts shield. If this causes the triggering attack to miss, the mage can spend a sorcery point to immediately force the attacker to repeat the attack against a creature the mage can see within 30 feet of them.
Mirror Mage (Standard)
Medium humanoid (any), any alignment
Armor Class 12 (15 With Mage Armor)
Hit Points 75 (10d8+30)
Speed 30 ft.
STR 12 (+1) DEX 14 (+2) CON 16 (+3)
INT 12 (+1) WIS 14 (+2) CHA 16 (+3)
Saving Throws Con +7, Cha +7
Skills Arcana +5, Deception +7, History +5, Perception +6
Senses passive Perception 16
Languages Any four languages
Challenge 10 (5900 XP)
Proficiency Bonus +4
Spellcasting. The mage is a 9th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 15, +7 to hit with spell attacks). The mage has the following sorcerer spells prepared:
Cantrips (At-Will): fire bolt, message, minor illusion, prestidigitation, ray of frost.
Metamagic: Distant Spell. The mage spend a sorcery point to double the range of a spell they cast if its range is 5 or more feet, or make a spell with a range of touch have a range of 30 feet instead.
Metamagic: Subtle Spell. The mage can spend a sorcery point to cast a spell without somatic or verbal components.
Metamagic: Twinned Spell. The mage copies a spell they cast, which can only have one target, by spending Sorcery Points equal to the spell slot spent. They must choose a new target for the copy.
Metamagic: Mirror Abjuration. The mage can spend a sorcery point whenever they cast shield, mirror image, or counterspell for additional effects (listed in Actions and Reactions).
Bonus Actions
Refract Cantrip. When the mage casts a cantrip that does damage to a single target, they can use a bonus action to choose a second target for the cantrip. If the secondary target takes damage from the cantrip, they take half as much damage instead.
Fire Bolt (Cantrip). Ranged Spell Attack: +7, Range 120 ft., one target. Hit: 11 (2d10) fire damage.
Ray of Frost (Cantrip). Ranged Spell Attack: +7, Range 60 ft., one target. Hit: 9 (2d8) cold damage. The target’s movement speed is reduced by 10 feet until the start of the mage’s next turn.
Reflective Mirror Image (Costs a 2nd-Level Spell Slot). The mage casts mirror image. Whenever one of the spell's duplicates is hit with an attack, the attacker takes 7 (2d6) force damage.
Reactions
Reflective Shield (Costs a 1st-Level Spell Slot). The mage casts shield. If this causes the triggering attack to miss, the mage can spend a sorcery point to immediately force the attacker to repeat the attack against a creature the mage can see within 30 feet of them.
Reflective Counterspell (Costs a 3rd-Level Spell Slot). The mage casts counterspell. If they successfully counter the triggering spell, they can spend a sorcery point to cast the countered spell using their spell save DC and spell attack modifier, choosing new targets for the spell. If the spell's level is above the maximum spell level the mage knows, they must spend additional sorcery points equal to the difference.
Mirror Mage (Greater)
Medium humanoid (any), any alignment
Armor Class 12 (15 With Mage Armor)
Hit Points 119 (14d8+56)
Speed 30 ft.
STR 12 (+1) DEX 14 (+2) CON 18 (+4)
INT 12 (+1) WIS 14 (+2) CHA 18 (+4)
Saving Throws Con +9, Cha +9
Skills Arcana +6, Deception +9, History +6, Perception +7
Senses passive Perception 17
Languages Any four languages
Challenge 14 (11500 XP)
Proficiency Bonus +5
Spellcasting. The mage is a 14th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 17, +9 to hit with spell attacks). The mage has the following sorcerer spells prepared:
Cantrips (At-Will): fire bolt, message, minor illusion, prestidigitation, ray of frost.
6th-level Spells (1 slot): disintegrate, flesh to stone.
7th-level Spells (1 slot): prismatic spray.
Sorcery Points. The mage has 14 Sorcery Points.
Metamagic: Distant Spell. The mage spend a sorcery point to double the range of a spell they cast if its range is 5 or more feet, or make a spell with a range of touch have a range of 30 feet instead.
Metamagic: Subtle Spell. The mage can spend a sorcery point to cast a spell without somatic or verbal components.
Metamagic: Twinned Spell. The mage copies a spell they cast, which can only have one target, by spending Sorcery Points equal to the spell slot spent. They must choose a new target for the copy.
Metamagic: Mirror Abjuration. The mage can spend a sorcery point whenever they cast shield, mirror image, or counterspell for additional effects (listed in Actions and Reactions).
Bonus Actions
Refract Cantrip. When the mage casts a cantrip that does damage to a single target, they can use a bonus action to choose a second target for the cantrip. If the secondary target takes damage from the cantrip, they take half as much damage instead.
Fire Bolt (Cantrip). Ranged Spell Attack: +9, Range 120 ft., one target. Hit: 16 (3d10) fire damage.
Ray of Frost (Cantrip). Ranged Spell Attack: +9, Range 60 ft., one target. Hit: 13 (3d8) cold damage. The target’s movement speed is reduced by 10 feet until the start of the mage’s next turn.
Reflective Mirror Image (Costs a 2nd-Level Spell Slot). The mage casts mirror image and spends 1 sorcery point. Whenever one of the spell's duplicates is hit with an attack, the attacker takes 7 (2d6) force damage.
Reactions
Reflective Shield (Costs a 1st-Level Spell Slot). The mage casts shield. If this causes the triggering attack to miss, the mage can spend a sorcery point to immediately force the attacker to repeat the attack against a creature the mage can see within 30 feet of them.
Reflective Counterspell (Costs a 3rd-Level Spell Slot). The mage casts counterspell. If they successfully counter the triggering spell, they can spend a sorcery point to cast the countered spell using their spell save DC and spell attack modifier, choosing new targets for the spell. If the spell's level is above the maximum spell level the mage knows, they must spend additional sorcery points equal to the difference.
Mirror Mage (Major)
Medium humanoid (any), any alignment
Armor Class 12 (15 With Mage Armor)
Hit Points 171 (18d8+90)
Speed 30 ft.
STR 12 (+1) DEX 14 (+2) CON 20 (+5)
INT 12 (+1) WIS 14 (+2) CHA 20 (+5)
Saving Throws Con +11, Cha +11
Skills Arcana +7, Deception +11, History +7, Perception +8
Senses passive Perception 18
Languages Any four languages
Challenge 17 (18000 XP)
Proficiency Bonus +6
Spellcasting. The mage is an 18th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 19, +11 to hit with spell attacks). The mage has the following sorcerer spells prepared:
Cantrips (At-Will): fire bolt, message, minor illusion, prestidigitation, ray of frost.
Metamagic: Distant Spell. The mage spend a sorcery point to double the range of a spell they cast if its range is 5 or more feet, or make a spell with a range of touch have a range of 30 feet instead.
Metamagic: Subtle Spell. The mage can spend a sorcery point to cast a spell without somatic or verbal components.
Metamagic: Twinned Spell. The mage copies a spell they cast, which can only have one target, by spending Sorcery Points equal to the spell slot spent. They must choose a new target for the copy.
Metamagic: Mirror Abjuration. The mage can spend a sorcery point whenever they cast shield, mirror image, or counterspell for additional effects (listed in Actions and Reactions).
Silverwalk. Once during each of your turns, you can spend 5 feet of movement to enter a reflective surface and exit from another reflective surface within 60 feet of that one.
Bonus Actions
Refract Cantrip. When the mage casts a cantrip that does damage to a single target, they can use a bonus action to choose a second target for the cantrip. If the secondary target takes damage from the cantrip, they take half as much damage instead.
Fire Bolt (Cantrip). Ranged Spell Attack: +11, Range 120 ft., one target. Hit: 22 (4d10) fire damage.
Ray of Frost (Cantrip). Ranged Spell Attack: +11, Range 60 ft., one target. Hit: 18 (4d8) cold damage. The target’s movement speed is reduced by 10 feet until the start of the mage’s next turn.
Reflective Mirror Image (Costs a 2nd-Level Spell Slot). The mage casts mirror image and spends 1 sorcery point. Whenever one of the spell's duplicates is hit with an attack, the attacker takes 7 (2d6) force damage.
Create Duplicates (1/Day). The mage creates four identical duplicates of a creature they can see at empty spaces within 60 feet of them. Each duplicate has AC 19, 19 hit points, and is a construct creature. They have the same statistics and movement options as the target but lack all traits and unique actions of the target. During each of their turns, the mage can direct the duplicates' actions using a bonus action, and they act on the same initiative immediately after the mage's turn. Given no actions, they take the Dodge action. Each duplicate gains the following action.
Force Strike. Melee or Ranged Spell Attack: +11, Reach 5 ft. or Range 60 ft. Hit: 5 Force damage.
Reactions
Reflective Shield (Costs a 1st-Level Spell Slot). The mage casts shield. If this causes the triggering attack to miss, the mage can spend a sorcery point to immediately force the attacker to repeat the attack against a creature the mage can see within 30 feet of them.
Reflective Counterspell (Costs a 3rd-Level Spell Slot). The mage casts counterspell. If they successfully counter the triggering spell, they can spend a sorcery point to cast the countered spell using their spell save DC and spell attack modifier, choosing new targets for the spell. If the spell's level is above the maximum spell level the mage knows, they must spend additional sorcery points equal to the difference.
Glamour human veigar and yordle mirror mage Leblanc :]
I think it would be cool if that for 15 or so minutes veigar could hold onto this taller form but it destabilizes into a more terrifying version with this slimy consistency for skin. It also gets shorter which doesn’t help.
Also mirror mage is just Leblanc cosplaying as a yordle