TEXT: Version 2.0 @2018 Wizards of the Coast LLC. Permission granted to print and photocopy this document for personal use only.
  Errata: Monster Manual
  This document updates parts of the Monster Manual (5th edition) 
  of Dungeons & Dragons. All the updates here appear in the 
  10th printing of the book and in the 2018 core rulebook gift sets.
   When updates are added to this document, its version number 
  changes, and the word “New” appears before the latest material.
  Global
   Damage Resistances/Immunities. Throughout the book, in-
  stances of “nonmagical weapons” in Damage Resistances/Immu-
  nities entries have been replaced with “nonmagical attacks.”
  Introduction
   Vulnerabilities, Resistances, and Immunities (p. 8). The 
  second and third sentences now read as follows: “Particular crea-
  tures are even resistant or immune to damage from nonmagical 
  attacks (a magical attack is an attack delivered by a spell, a magic 
  item, or another magical source). In addition, some creatures are 
  immune to certain conditions.”
   Spellcasting (p. 10). The second paragraph ends with a new 
  sentence: “The monster is considered a member of that class 
  when attuning to or using a magic item that requires member-
  ship in the class or access to its spell list.”
   Legendary Creatures (p. 11). This section has been tightened 
  up to include the following new rules:
  • The opening has a new second paragraph: “If a creature 
  assumes the form of a legendary creature, such as through a 
  spell, it doesn’t gain that form’s legendary actions, lair actions, 
  or regional effects.”
  • The final sentence of the “Legendary Actions” section is now 
  two sentences: “It can forgo using them, and it can’t use them 
  while incapacitated or otherwise unable to take actions. If sur-
  prised, it can’t use them until after its first turn in the combat.”
  • The final sentence of the “Lair Actions” section is now three 
  sentences: “On initiative count 20 (losing all initiative ties), it 
  can use one of its lair action options. It can’t do so while inca-
  pacitated or otherwise unable to take actions. If surprised, it 
  can’t use one until after its first turn in the combat.”
  Monsters A to Z
  To aid reference, the following revisions are listed in alphabetical 
  order by monster name. If a change is to a stat block, the name of 
  the stat block entry is given, along with whatever changed in it.
   Aarakocra (p. 12). Languages: added Aarakocra.
   Acolyte (p. 342). Senses: passive Perception 12 [was 10].
   [New] Adult Blue Dracolich (p. 84). Saving Throws: Dex +6, 
  Con +12, Wis +8, Cha +10 [each was 1 lower]. Skills: Perception 
  +14 [was +12], Stealth +6 [was +5]. Senses: passive Perception 
  24 [was 22]. Bite, Claw, and Tail +13 to hit [was +12].
   Adult Brass Dragon (p. 105). Fire Breath: Avg. damage is 45 
  [was 49].
   Ancient Black Dragon (p. 87). XP: 33,000 [was 27,500].
   Ancient Blue Dragon (p. 90). XP: 50,000 [was 32,500].
   Ancient Brass Dragon (p. 104). XP: 25,000 [was 24,500].
   Ancient Bronze Dragon (p. 107). XP: 41,000 [was 30,000].
   Ancient Copper Dragon (p. 110). XP: 33,000 [was 27,500].
   Ancient Gold Dragon (p. 113). XP: 62,000 [was 36,500].
   Ancient Green Dragon (p. 93). XP: 41,000 [was 30,000].
   Ancient Red Dragon (p. 97). XP: 62,000 [was 36,500].
   Ancient Silver Dragon (p. 116). XP: 50,000 [was 32,500].
   Ancient White Dragon (p. 100). XP: 25,000 [was 24,500].
   Ankheg (p. 21). Bite: Avg. damage is 10 [was 9].
   Assassin (p. 343). Saving throws: Dex +6, Int +4 [each was 1 
  higher]. Skills: Acrobatics +6 [was +7], Deception +3 [was +4], 
  Perception +3 [was +4], Stealth +9 [was +11]. Senses: passive 
  Perception 13 [was 14]. Sneak Attack: Avg. damage is 14 [was 
  13]. Shortsword and light crossbow: +6 to hit [was +7].
   Banshee (p. 23). Saving throws: Cha +5 [was +4]. Detect Life: 
  “living creatures up to 5 miles away” is now “creatures up to 5 
  miles away that aren’t undead or constructs.”
   Barlgura (p. 56). Speed: 40 ft., climb 40 ft. [each was 30 ft.].
   Beholder Zombie (p. 316). Condition immunities: 
  added prone.
   [New] Black Bear (p. 318). Bite and Claws: +4 to hit [was +3].
   [New] Brown Bear (p. 319). Bite and Claws: +6 to hit [was +5].
   Cloud Giant (p. 154). Saving throws: Con +10 [was +9].
   Cult Fanatic (p. 345). Senses: passive Perception 11 [was 10].
   [New] Demilich (p. 48). Hit points: 80 (32d4) [was 20d4].
   Death Knight (p. 47). Added an “Undead Nature” section to 
  its description: “A death knight doesn’t require air, food, drink, 
  or sleep.”
   Deva (p. 16). Skills: Insight +9 [was +7].
   Diseased Giant Rat (p. 327). Bite: +4 to hit, 4 (1d4 + 2) damage 
  [each was 1 lower].
   Doppelganger (p. 82). Ambusher: now reads, “In the first 
  round of a combat, the doppelganger has advantage on attack 
  rolls against any creature it surprised.”
   Dragon Turtle (p. 119). Saving throws: Dex +6, Con +11, Wis 
  +7 [each was 1 lower]. Bite, Claw, and Tail: +13 to hit [was +12].
   Drider (p. 120). Longbow: range 150/600 ft. [was 120/600].
   Drow Elite Warrior (p. 128). Shortsword: reach 5 ft. [was 
  10 ft.].
   Druid (p. 346). Quarterstaff: 6 (1d8 + 2) damage with shille-
  lagh [was 1d8].
   [New] Efreeti (p. 145). Innate Spellcasting: “3/day” changed to 
  “3/day each.”
   Elephant (p. 322). Gore: 19 (3d8 + 6) [was 3d8 + 5]. Stomp: 22 
  (3d10 + 6) damage [was 3d10 + 5].
   Empyrean (p. 130). XP: 50,000 [was 32,500].
   Ettercap (p. 131). Web: the webbing is vulnerable to fire dam-
  age and immune to bludgeoning damage.
   Flameskull (p. 134). Speed: it can hover. Condition immuni-
  ties: added prone.
   Flying Sword (p. 20). Speed: it can hover.
   Ghost (p. 147). Speed: it can hover.
   [New] Gith (p. 159). In the “Red Dragon Riders” section, “Gith 
  returned” is changed to “Vlaakith returned.”
   Goblin Boss (p. 166). Javelin: +2 to hit, 3 (1d6) damage [each 
  was 2 higher].
   Gold Dragon Wyrmling (p. 115). Saving throws: Con +5 
  [was +6].
   [New] Gray Slaad (p. 277). Skills: Perception +7 [was +6]. 
  Senses: passive Perception 17 [was 16].
   [New] Grell (p. 172). Beak: “one creature” is changed to “one 
  target.”
   Gynosphinx (p. 282). Skills: Arcana +12, History +12 [each 
  was 2 higher], Perception +8, Religion +8 [each was 1 higher]. 
  Senses: passive Perception 18 [was 19]. Spellcasting: spell save 
  DC 16, +8 to hit with spell attacks [each was 1 higher]. Claw: +8 
  to hit [was 1 higher]. Teleport: up to 120 feet [was 12 feet].
   Guard (p. 347). Spear: Added “or 5 (1d8 + 1) piercing damage 
  if used with two hands to make a melee attack.”
   Half-Dragon (p. 180). Cut the Saving Throws line and the 
  Parry ability from the stat block. Added the following about chal-
  lenge rating: “To avoid recalculating the creature’s challenge rat-
  ing, apply the template only to a creature that meets the optional 
  prerequisite in the Breath Weapon table below. Otherwise, use 
  
  Version 2.0 @2018 Wizards of the Coast LLC. Permission granted to print and photocopy this document for personal use only.
  the guidelines in the Dungeon Master’s Guide to recalculate the 
  rating after you apply the template.”
  Size
  Breath Weapon
  Optional Prerequisite
  Large or smaller
  As a wyrmling
  Challenge 2 or higher
  Huge
  As a young dragon
  Challenge 7 or higher
  Gargantuan
  As an adult dragon
  Challenge 8 or higher
   Harpy (p. 181). Luring song: “the target can take the Dash 
  action on its turn to move …” is now “the target must move on 
  its turn …”
   [New] Hook Horror (p. 189). Senses: darkvision 120 ft. 
  [was 10 ft.]
   Horned Devil (p. 74). Hit points: 178 (17d10 + 85).
   Intellect Devourer (p. 191). Body thief: Appended this to the 
  first sentence: “… that isn’t protected by protection from evil and 
  good.” Later, “the host body drops to 0 hit points” is now “the 
  host body dies.”
   Kenku (p. 194). Ambusher: now reads, “In the first round of a 
  combat, the kenku has advantage on attack rolls against any crea-
  ture it surprised.”
   Kraken (p. 197). Saving throws: Str +17, Dex +7, Con +14, Int 
  +13, Wis +11 [each was 1 higher]. Bite and Tentacle: +17 to hit 
  [each was 1 higher].
   Kuo-toa Archpriest (p. 200). Unarmed strike: 5 (1d4 + 3) [was 
  1d4 + 2].
   [New] Lich (p. 202). Disrupt Life: “living creature” is now “non-
  undead creature.” Skills: Arcana +19 [was +18].
   [New] Lycanthropes (p. 207). In the “Player Characters as 
  Lycanthropes” sidebar, the start of the second paragraph now 
  reads, “A non-lycanthrope humanoid hit …”
   Magmin (p. 212). Touch: “creature” is now “target.”
   Merrow (p. 219). Senses: passive Perception 10 [was 12].
   Monodrone (p. 224). Javelin: +2 to hit, 3 (1d6) damage [each 
  was 1 higher].
   Night Hag (p. 178). Innate spellcasting: spell save DC 14, 
  +6 to hit with spell attacks [each was 1 lower]. Claws: +7 to hit 
  [was +6].
   Noble (p. 348). Senses: passive Perception 12 [was 10].
   Orc War Chief (p. 246). Greataxe: One target [was one crea-
  ture], and avg. damage is 15 [was 14].
   Otyugh (p. 248). Tentacle slam: Constitution saving throw [was 
  Strength saving throw].
   [New] Priest (p. 348). Speed: 30 ft. [was 25 ft.]. Skills: Religion 
  +5 [was +4].
   [New] Purple Worm (p. 255). Bite and Tail Stinger: +14 to hit 
  [each was +9].
   Quaggoth (p. 256). Senses: passive Perception 11 [was 10].
   Rakshasa (p. 257). Limited magic immunity: the first sentence 
  now reads, “The rakshasa can’t be affected or detected by spells 
  of 6th level or lower unless it wishes to be.”
   [New] Revenant (p. 259). Rejuvenation: “animates another 
  corpse” is changed to “animates another humanoid corpse.”
   Riding Horse (p. 336). Hooves: +5 to hit [was +2].
   Solar (p. 18). Slaying longbow: range 150/600 ft. [was 
  120/600].
   Swarm of X (p. 337–39). Condition immunities: every swarm 
  is immune to being grappled.
   [New] Thri-kreen (p. 288). Bite: the last sentence now reads, 
  “The poisoned target can repeat the saving throw at the end of 
  each of its turns, ending the effect on itself on a success.”
   Troll (p. 291). Skills: Perception +2 [was +1]. Senses: Passive 
  perception 12 [was 11].
   Vampire, Spellcaster (p. 298). Spellcasting: spell save DC 16, 
  +8 to hit with spell attacks [each was 1 lower].
   Veteran (p. 350). Heavy crossbow: 6 (1d10 + 1) damage 
  [was 1d10].
   Warhorse (p. 340). Hooves: +6 to hit [was +4].
   Water Elemental (p. 125). Whelm: added the word “check” af-
  ter “DC 14 Strength” in the final sentence.
   [New] Werewolf (p. 211). Multiattack (Humanoid or Hybrid 
  Form Only) now reads, “The werewolf makes two attacks: two 
  with its spear (humanoid form) or one with its bite and one with 
  its claws (hybrid form).”
   Will-o’-Wisp (p. 301). Invisibility: the reference to “Life Drain” 
  is now to “Consume Life.”
   Young Brass Dragon (p. 105). Saving throws: Dex +3, Con +6, 
  Wis +3, Cha +5 [each was 2 higher]. Skills: Perception +6 [was 
  +10], Persuasion +5 [was +7], Stealth +3 [was +5]. Senses: pas-
  sive Perception 16 [was 20]. Bite and Claw: +7 to hit [was +9].
  
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