Mortalita is definitely not a fighter, she has magical powers but uses them to protect rather than to fight.
Mortalita is actually referenced in many ancient human rituals and is usually referred to as a goddess of fertility and the giver of all life. This is naturally false, but she is the mother of Life(a girl representing all of living beings) so she can be referred to as the mother of all life.
She is also referred to in some rather dark rituals as the mother of death, this is also accurate as she is the mother of Death and Shi(two of the most active reapers).
Her species is rather mysterious, she isn't identifiable as a reaper, human or deity.
Her origins are mysterious as well.
Mortalita's powers aren't so mysterious. She can use a primordial force of nature in a form of an invisible energy.
This energy if used as a shield is impenetrable and if used as a weapon, it pierces through anything in its path.
If she ever needs to attack, she does weird movements with her hands and pushes them forward, shooting this invisible energy which is instantaneous and anything in its path is destroyed.
She can make these "blasts" of varying size and power.
The "blasts" can also pierce through other attacks like lasers and fire
