To unlock Nightmare mode, one must complete all of the missions on the planet (except for Mercury, which was removed from the Nightmare Mode pool in Update 9.2). You also cannot start a Nightmare mode mission if your Mastery Rank is 0.
From Update 11 onwards you may choose whether to run the mission in Nightmare Mode or not. If some of the players in given cell do not have Nightmare Mode unlocked, only those with it unlocked should select Nightmare Mode or else the mission will start normally.
The rewards for this mode are randomized, so a player can complete the same mission repeatedly for a different reward.
All Nightmare Mode enemies are significantly increased in level and damage output, and in some cases are replaced with more dangerous versions. For example, instead of spawning Grineer Lancers, the map may spawn more Elite Lancers in their place. In Nightmare mode, lockers won't drop ammo but enemies still will. Environmental Hazards can also appear as usual.
Up to two of the following challenges may occur per mission, and each modifier has an equal chance of being selected:
|No Shields||All player shields are reduced to zero.||
|Timer||The mission has a 5-minute timer that will fail the mission if it runs down. Killing enemies will add 5 seconds to the timer.||
|Health Vampire||Players will lose 1.5% of their maximum health every second, Killing enemies will recover 12.5% of their maximum health for the entire cell.||
|Energy Drain||Players will steadily lose energy at approximately 5 points per second.||
|Lethal Explosive Barrels||Explosive Barrels will now deal high, if not fatal damage.||
|Longer Reload||Reload times are increased by ~50%||
In addition to the challenges above there is also a 50% chance of low gravity taking effect, which will affect everything including player maneuvers in the air, enemies and loot. A similar effect can be found in Hive Sabotage missions when destroying a Stabilizing Infested Hive.
- Main article: Category:Nightmare Mode Mods
Possible rewards on completion include:
- Nightmare Defense missions require players to finish a set amount of waves to complete the mission.
- Update 9.7 added the mod rewards from the Arid Fear Event (Shred, Vigor and Lethal Torrent) in Nightmare Mode's reward pool.
- At the time of Nightmare Mode's introduction there was a No Minimap modifier that also removed the objective indicator. This was removed in Update 9.4 following player complaints
- Update 9.4 added the No Shields modifier to the Energy Drain modifier, as well as reducing the chance of getting the combined modifier. Update 11.5.4 simply split the modifiers altogether.
- Host Migration will sometimes revert the mission to a normal state, removing all modifiers and resetting enemy levels to the mission's original range. Nightmare mods will still be rewarded however.
- The Health Vampire and Timer modifiers will take effect as soon as the mission begins, i.e. as soon as the beginning cutscene starts.
|Assassination • Capture • Conclave • Deception • Defense • Excavation • Exterminate • Hijack • Interception • Invasion (Solar Rail) • Mobile Defense • Recovery • Rescue • Sabotage (Hive) • Spy • Survival|
|Relay • Quest • PvP • Environmental Hazards • Nightmare Mode • Tile Sets • Alerts|