Deep nightmare - Seven Knights Idle Adventure
Deep Nightmare is a game mode where you must face bosses, one boss per tier, with three different teams.
To pass the stage, you must defeat the boss with each of your teams.

How to unlock it
You unlock Deep Nightmare once you have completed tier 30 of Nightmare mode.

Information
The Nightmare shard bonuses are also active in this game mode.
There is no access limit in this mode; you can restart a battle an infinite number of times.
Each team consists of 15 heroes. Depending on the number of tiers you manage to pass, this mode can become your main source of elixir.
Currently, this game mode is the most time-consuming because you cannot skip battles.
In addition, you must complete 3 battles per tier.
Fortunately, the developers are working on a solution: More information in this developer note.
Tips
You must defeat the boss with each of your teams, so you need to build 3 balanced teams.
Note that the further you progress, the more the boss will have dodge and critical resistance.
Each of your teams must have the core buffs and debuffs:
In addition, it is important to have one hero per team who boosts damage against bosses in Nightmare mode:
- Velika (+50% damage nightmare Boss)
- Medea (+50% damage nightmare Boss)
- Alcyion (+50% damage nightmare Boss)
- High Lord Sun Wukong (+70% damage nightmare Boss)
- High Lord Orly (+80% damage nightmare Boss)
Some bosses have a healing buff, so it's also important to choose a hero who can remove buffs from bosses.
Equip each team with one or more heroes with attacks that hit multiple times, as some bosses have a veil buff (20 attacks canceled).
Raise your Nightmare Shard level (or rather, wait for it to rise).
Solve the critical hit resistance problem.
At first, critical hit resistance will not pose any problems, but it will quickly prove to be a real challenge.

Critical hit rate resistance on boss
This type of game mode is why it's useful to have heroes with critical hit potential rolls.
Since the release of the Awakening heroes, add a hero with a 36% critical hit rate buff, such as Awakening Rachel.
Add a hero that applies the debuff reducing critical hit rate resistance to 36%, such as Bloody Night Kyle or Cat Mage Lucia.
Wait for level 30 of Nightmare shard to get a critical hit rate increase to 50% for all of your heroes.

The hardest part is often applying the first decrease critical hit rate resistance debuff.
This is because at the start of the battle, your heroes are not buffed and may miss their critical hits and therefore fail to apply their buffs.
(Of course, this is in cases where the hero's buffs are applied via critical hits.)
Use aura
The solution is to use a hero with an aura that increases the crit rate.
This will increase the crit hit rate for all heroes without having to touch the boss, so more chances to apply decrease critical hit resistance.
Vicky is the only hero with this ability.
Use active skill
An another solution is to use a hero with a decrease crit rate resistance debuff on their active skill.
Even if it is 20% (instead of 24%), this will allow you to rely solely on your accuracy to apply the debuff.
In the case of a reduction to only 20%, it is still important to have a second hero at 24%.
Michaela and Taka have this ability.
Teams Deep nightmare (Update January 2026)
I use a general team so that I can take on all bosses and save time.
There is not much to add about the teams; they are simply teams created based on the Tips section above.
To optimize further, you can create a team for each type of boss.
Rewards
For each tier you complete, you will receive 300 elixirs and 300 power tokens.
Every 10 tiers, you will receive a copy of the hero Alcyion.
From tier 100 onwards, power tokens are replaced by 5,000 gold dice.
Reset
Please note that progress in this game mode is reset every 14 days after the update, as in Nightmare mode.
This site is a fan project and is not affiliated with, sponsored by, or endorsed by Netmarble.
All names, logos, and images are the property of their respective owners.