Gametitle-FO4 NW
Gametitle-FO4 NW

Aeternus is a unique weapon in the Fallout 4 add-on Nuka-World.


Aeternus is a unique Gatling laser that bears the "Never Ending" legendary effect.

Although it uses the "Never Ending" effect, its actual effect gives the weapon true unlimited ammo. It will use a portion of a fusion core when first fired, but the core's charge will not decrease again while using Aeternus.



Carried by the rogue knight during the quest Amoral Combat. The quest must be repeated until the rogue knight is the challenger. Upon their defeat, they will drop Aeternus.

Related questEdit


If the user has one or two fusion cores in the inventory, Aeternus will fire off 1 or 2 rounds before fully depleting the cores. If one has at least three fusion cores, the fresh loaded weapon will use a seemingly random portion of one fusion core before reaching "unlimited ammunition." This is valid up until one loads a new fusion core either by equipping another weapon, modifying the Aeternus in a weapons workbench, or increasing the amount of fusion cores in ones inventory.

When firing the Aeternus with a fresh fusion core, the shown ammo will always become 1 less than all the fusion cores ones inventory. The remaining charge of the active fusion core is not equivalent to this number. If the maximum number of fusion cores in ones inventory is 1, the ammunition in the clip will become 0, causing the fusion core to deplete and vanish. As such, the Aeternus is nearly completely useless if one has only 1 fusion core in their inventory. Additionally, if the amount of fusion cores in ones inventory increases while the Aeternus is out, the current fusion core will instantly be consumed and the clip's ammo will become equal to the remaining fusion cores in ones inventory, then decrease by 1 when you fire the Aeternus again.

Behind the scenesEdit

The weapon's name is from the Latin language, meaning "eternal" or "immortal."


  • ps4Icon ps4 Consumes 33% of a fusion core on the first shot, then nothing for the rest of its use. If the gun is put away or switched, it has a new fusion core automatically inserted which takes another 33% of the cores charge on its first shot. This can leave a regular user with a large stack of fusion cores with only 67% charge. Once the player is out of full-charge fusion cores the gun will automatically load the partially depleted cores, which will then fully deplete the fusion cores, though they still function in the gun.[verified]
    • To fix this, keep all but one fusion core stashed on a companion or in a container.
  • pcIcon pc ps4Icon ps4 xboxoneIcon xboxone It seems to be irregular in consuming ammo. Sometimes draining a fusion core entirely in the first shots, or firing only as many shots as the player has fusion cores and then removing one core entirely. [verified]
  • pcIcon pc Used cores randomly deplete to under 10 power then switch to a new core. As the ammo counter shows how many cores one has this is misleading as it gives the appearance of having infinite cores, until one sees all their cores have anywhere from 3-9 uses left. [verified]