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@@ -2396,6 +2396,61 @@ The dragon can take 3 legendary actions, choosing from the options below. Only o
 
 ### Green Dragon
 
+#### Ancient Green Dragon
+
+*Gargantuan dragon, lawful evil*
+
+**Armor Class** 21 (natural armor)
+
+**Hit Points** 385 (22d20 + 154)
+
+**Speed** 40 ft., fly 80 ft., swim 40 ft.
+
+| STR     | DEX     | CON     | INT     | WIS     | CHA     |
+|---------|---------|---------|---------|---------|---------|
+| 27 (+8) | 12 (+1) | 25 (+7) | 20 (+5) | 17 (+3) | 19 (+4) |
+
+**Saving Throws** Dex +8, Con +14, Wis +10, Cha +11
+
+**Skills** Deception +11, Insight +10, Perception +17, Persuasion +11, Stealth +8
+
+**Damage Immunities** poison
+
+**Condition Immunities** poisoned
+
+**Senses** blindsight 60 ft., darkvision 120 ft., passive Perception 27
+
+**Languages** Common, Draconic
+
+**Challenge** 22 (41,000 XP)
+
+***Amphibious***. The dragon can breathe air and water.
+
+***Legendary Resistance (3/Day)***. If the dragon fails a saving throw, it can choose to succeed instead.
+
+***Multiattack***. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
+
+***Bite***. *Melee Weapon Attack:* +15 to hit, reach 15 ft., one target. *Hit:* 19 (2d10+8) piercing damage plus 10 (3d6) poison damage.
+
+***Claw***. *Melee Weapon Attack:* +15 to hit, reach 10 ft., one target. *Hit:* 22 (4d6+8) slashing damage.
+
+***Tail***. *Melee Weapon Attack:* +15 to hit, reach 20 ft., one target. *Hit:* 17 (2d8+8) bludgeoning damage.
+
+***Frightful Presence***. Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 19 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours.
+
+***Poison Breath (Recharge 5-6)***. The dragon exhales poisonous gas in a 90-foot cone. Each creature in that area must make a DC 22 Constitution saving throw, taking 77 (22d6) poison damage on a failed save, or half as much damage on a successful one.
+
+###### Legendary Actions
+
+The dragon can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The dragon regains spent legendary actions at the start of its turn.
+
+**Detect**. The dragon makes a Wisdom (Perception) check.
+
+**Tail Attack**. The dragon makes a tail attack.
+
+**Wing Attack (Costs 2 Actions)**. The dragon beats its wings. Each creature within 15 feet of the dragon must succeed on a DC 23 Dexterity saving throw or take 15 (2d6+8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.
+
+
 #### Adult Green Dragon
 
 *Huge dragon, lawful evil*
@@ -8527,4 +8582,4 @@ Saving Throws Wis +0
 
 ###### Actions
 
-***Morningstar***. *Melee Weapon Attack:* +6 to hit, reach 5 ft., one target. *Hit:* 13 (2d8+4) bludgeoning damage.
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+***Morningstar***. *Melee Weapon Attack:* +6 to hit, reach 5 ft., one target. *Hit:* 13 (2d8+4) bludgeoning damage.