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These descriptions are intended to summarize, not replace, entries in the Players Handbook in an objective manner.
Added
New in PHB24
Arcane Vigor (p. 242)
Wizards and Sorcerers get a Level 2 spell that lets them use up to two of their available Hit Point Dice to heal for the result plus spellcasting modifier as a Bonus Action. Upcasting lets them add 1 Hit Point Die per spell slot level.
Befuddlement (p. 245)
Target rolls Intelligence save or takes 10d12 Psychic and loses ability to use any magic for 30 days before being able to repeat the save. Half damage and no other effects on a successful save
Appears to be a replacement for the legacy, removed Feeblemind spell, but does not impair the target’s Intelligence.
Divine Smite (p. 265)
Previously a class Feat for the Paladin, this is now a Leveled spell in order to align it with the other smite types and prevent the “double smite” exploit. Can only be cast after a successful Melee or Unarmed Strike, does bonus 1d8 against Fiends and Undead.
Elementalism (p. 267)
An elements-themed utility cantrip similar to Druidcraft or Thaumaturgy that’s available to the Sorcerer and Wizard classes.
Fount of Moonlight (p. 276)
Level 4 spell that illuminates space, buffs its caster with Radiant Resistance and bonus 2d6 Radiant damage, and can apply Blinded to an attacker as a Reaction.
Jallarzi’s Storm of Radiance (p. 289)
Mechanically similar to Spirit Guardians, it debuffs creatures inside its area with Blinded, Deafened, and prevents casting any spells with Verbal components.
Power Word Fortify (p. 306)
Level 7 buff spell granting a pool of 120 Temporary HP to be divided among its targets.
Shining Smite (p. 316)
A new Paladin smite that does 2d6 Radiant and illuminates its target, granting Advantage to attacks against it and negating any benefit of Invisible.
Sorcerous Burst (p. 318)
Ranged attack cantrip that does 1d8 Acid, Cold, Fire, Lightning, Poison, Psychic, or Thunder - caster’s choice. Has a rolling bonus damage mechanic that adds damage dice when the rolled result is an 8. The number of damage dice increase at character levels 5, 11, and 17.
Starry Wisp (p. 320)
Ranged spell attack dealing 1d8 Radiant illuminating the target and negating benefits of Invisible.
Tasha’s Bubbling Cauldron (p. 330)
Level 6 Conjuration that allows for the production of a number of Common or Uncommon potions equal to the caster’s spellcasting modifier. This spell has a material component cost that cannot be avoided with an Arcane Focus.
Yolande’s Regal Presence (p. 343)
Creates an Emanation around the caster and forces a Wisdom saving throw to avoid 4d6 Psychic, Prone, and being pushed up to 10 feet away, half damage only on a successful save.
Imported from Prior Books
Charm Monster (p. 249)
Functionally identical to Charm Person, but works on non-humanoid creatures and is a Level 4 Enchantment rather than Level 1
Originally appeared in Xanathar’s Guide to Everything.
Dragon’s Breath (p. 266)
Grants an elemental breath weapon attack to a creature on touch. Creatures within its 15’ Cone make a Dexterity saving throw or take 3d6 of the chosen elemental damage, half that on a save
Originally appeared in Xanathar’s Guide to Everything.
Ice Knife (p. 287)
Ranged spell attack that does 1d10 Piercing to its target then explodes, forcing a Dexterity saving throw to avoid 2d6 Cold.
Originally appeared in Elemental Evil Player’s Companion.
Mind Sliver (p. 298)
Cantrip that forces Intelligence saving throw to avoid 1d6 Psychic damage and 1d4 penalty to target’s next saving throw in the current round.
Originally appeared in Tasha’s Cauldron of Everything.
Mind Spike (p. 298)
Target takes 3d8 Psychic and has its location known to the caster for 1 hour on a failed Wisdom saving throw, half damage on a success.
Originally appeared in Xanathar’s Guide to Everything.
Steel Wind Strike (p. 322)
Level 5 Conjuration that lets the caster make a melee spell attack to deal 6d10 Force to each of up to 5 creatures in its area, then teleport to within 5 feet of any of those targets regardless of whether they were hit.
Originally appeared in Xanathar’s Guide to Everything.
Summon Aberration (p. 322)
Manifests an allied Beholderkin, Slaad, or Star Spawn (caster’s choice) Aberrant Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Beast (p. 322)
Manifests an allied Air, Land, or Water (caster’s choice) Bestial Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Celestial (p. 323)
Manifests an allied Avenger or Defender(caster’s choice) Celestial Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Construct (p. 324)
Manifests an allied Clay, Metal, or Stone (caster’s choice) Construct Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Dragon (p. 324)
Manifests an allied Draconic Spirit for 1 hour.
The PHB24 version of this spell removes the earlier version’s choice of the dragon’s type.
Originally appeared as Summon Draconic Spirit in Fizban’s Treasury of Dragons.
Summon Elemental (p. 325)
Manifests an allied Air, Earth, Fire, or Water (caster’s choice) Elemental Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Fey (p. 326)
Manifests an allied Fuming, Mirthful, or Tricksy (caster’s choice) Fey Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Fiend (p. 326-327)
Manifests an allied Demon, Devil, or Yugoloth (caster’s choice) Fiendish Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Summon Undead (p. 328)
Manifests an allied Ghostly, Putrid, or Skeletal (caster’s choice) Undead Spirit for 1 hour.
Originally appeared in Tasha’s Cauldron of Everything.
Synaptic Static (p. 330)
Creatures in its area make an Intelligence saving throw to take half damage, otherwise they take 8d6 Pyschic and have a 1d6 penalty their attacks, ability checks, and Concentration saves for 1 minute. The Intelligence saving throw can be repeated at the end of the afflicted creature’s turn to end the effect.
Originally appeared in Xanathar’s Guide to Everything.
Thunderclap (p. 330)
Creatures within 5 feet of the caster must succeed on a Constitution saving throw or take 1d6 Thunder.
Originally appeared in Elemental Evil Player’s Companion.
Toll the Dead (p. 334)
The target of this cantrip must succeed on a Wisdom saving throw or take 1d8 Necrotic. If the target was missing any HP, the damage is 1d12 Necrotic instead.
Originally appeared in Xanathar’s Guide to Everything.
Vitriolic Sphere (p. 337)
Deals 10d4 Acid when cast and another 5d4 Acid to each creature caught in its area at the end of their next turn. If a creature in the area succeeds on a Dexterity saving throw, it only takes half of the initial damage.
Originally appeared in Elemental Evil Player’s Companion.
Word of Radiance (p. 343)
Creatures within 5 feet of the caster make a Constitution saving throw to avoid 1d6 Radiant.
Originally appeared in Xanathar’s Guide to Everything.
Removed
Feeblemind (PHB14 p. 239)
Appears to have been replaced by the newly-added spell Befuddlement, which damages the opponent but does not impair their abilities.