The Nightmare Chest is a limited time
treasure chest offered in Castle Age. It costs 30 FP for one item pull from the chest and 80 FP for 3 pulls. It is available for players of all levels.
It was introduced on September 28, 2018 with a limited time of 168 hours (1 week) to use it.
It also differs from the other chests in that there is a "Legendary" section. You have a 1% chance to pull a "Legendary" reward.
Chest contents & Items rarity
1% chance to pull an item from this tier. Composed exclusively of heroes (previously rewards from Arena seasons 10 and 11).
X% chance to nullify opponent Pierce/Resist
Master: +40% Clone of Alliance General Ability
5% chance to pull an item from this tier. Composed exclusively of heroes (previously rewards from Arena seasons 6 to 9).
+X Attack based on 10% of Player's Divine Power (Divine Power = 36)
50 Physical Piercing (Divine Power = 40)
Nax the Blighted
+5% to Attack Rune Drain. Max 30% (Divine Power = 70)
+X% to Mage skill Fireball damage, +Y to Fire Offense, +Z Physical Pierce
10% chance to pull an item from this tier. Composed exclusively of heroes.
Increases Player Attack by X against monsters, based on level
When attacked in guild battle, a flat X damage and Y% of your Damage Rune is deflected back on the attacker
+X Damage and +Y% Damage Rune bonus in Guild Battles
Petrus the Elusive
+X% to Rogue skill Smoke Bomb, +Y to Earth Resistance, +Z to Physical Resistance
30% chance to pull an item from this tier. Composed exclusively of heroes (which had not been obtainable for a long time before this chest).
Increases Player Attack by X and decreases Max Energy by Y
X% chance to receive extra Demi Points from battles, and monster battles
Decreases opposing War Council's defense by X
Increases Max Stamina by X
54% chance to pull an item from this tier. Composed of 5 Consumables and 3 Artifacts.
Note: It appears you get more than one item when you get a drop from this tier, even though it isn't indicated in game (in fact the text after rolling even says otherwise):
Evolution Crystals: x3
Hero Potions: x3
Refine Crystals: x2
Enhance Crystals: x2
Sept. 28, 2018 with a limited time of 168 hours (7 days)
Dec. 26, 2018 with a limited time of 144 hours (6 days)
Feb. 24, 2019 with a limited time of 120 hours (5 days)
Apr. 4, 2019 with a limited time of 120 hours (5 days)
Dec. 28, 2019 with a limited time of 144 hours (6 days)
This chest doesn't include any new item or hero. It only gathers heroes which were previously obtainable through diverse means: Arenas, Events (current and discontinued) and Legendary General Chest, World Monster, limited time promotions, discontinued Favor Generals, Limited Time Alchemy Recipe, etc.
The actual drop rates may be much worse than the advertised drop rates, with much more Common tier drops: Nightmare Chest Drop Rates (forums post).
You get more than one item when you get a Common tier drop, at least since the 5th occurrence of this chest. It might have been the case before, but it was never reported (the text when you get a drop says you get only one item even though you actually get more). It might also have been the case with the Anniversary Chest.
Introduced on September 28, 2018 at 0:00 PST (7:00 am UTC on the 28th).
To check when this event occurred in the past, see this page: Events Rotation.
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