Although it uses the "never ending" legendary 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.
pcps4 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.
Used cores randomly deplete to under 10 power then switch to new core, as the ammo counter shows how many cores you have this is misleading as yo think you have infinite, till you see all your core have from 3-9 use left. [platforms tag needed][verification needed]
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