The Ancient Nightmare quest is a zone event that can be completed in the Mount Zavain area to obtain various rewards in Diablo Immortal. To unlock zone events, players will need to reach level 60 and complete all of the campaign quests. The Ancient Nightmare event requires players to enter the Mount Zavain zone on Hell difficulty, and it can be completed solo or while in a party.
Zone events are quests specific to each region, and they can be completed multiple times a day depending on when they're available and what the cooldown time is. Zone events like Ancient Nightmare or Haunted Carriage in Diablo Immortal are only active during specific timeframes based on local server time. Additionally, most of the zone events have cooldown periods, so missing the quest will result in waiting around for a few hours until it's active again.
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The Ancient Nightmare event can be completed every two hours from 8 am to midnight. The event starts on the hour, and if players are already in the Mount Zavain zone, a prompt will appear asking if they want to participate. Accepting the prompt will reveal a highlighted path leading to the event, but players can also simply travel to the Misty Valley area near the center of the Mount Zavain zone. To complete the event, the Ancient Nightmare boss needs to be defeated using the altars scattered around the zone.
The challenge for completing the Ancient Nightmare zone event in Diablo Immortal is activating the altars and depleting the enemy's shield. Players should be familiar with the altars that emit light throughout the Mount Zavain zone because they were used during one of the campaign missions. Activating an altar
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