The Mimics are the main antagonists in Edge of Tomorrow and All You Need is Kill.
They are a race of brutal alien invaders that seek to conquer different planets throughout the galaxy. They are led by the Omega, which can alter time in order to learn and adapt to their enemy's battle tactics in order to swiftly overpower and destroy whatever stands in their way.
Edge of Tomorrow (Movie)
An officer finds himself caught in a time loop in a war with an alien race. His skills increase as he faces the same brutal combat scenarios, and his union with a Special Forces warrior gets him closer and closer to defeating the enemy. Eventually Cage leads an assault on the Omega, the Mimic Hive Mind in Paris, France. Though everyone dies in the attempt, Cage manages to kill the Omega with a belt of grenades. The Mimics die with it. Though the Omega's blood restores Cage's lost ability to reset the day, he finds when he wakes up the day before, the Omega's death and the Mimics defeat followed him through time.
All You Need is Kill (Manga)
The world is in a war against an alien race called "Mimics," who have taken over most of the world with a mission to eliminate the human race. Keiji Kiriya is a new recruit in the United Defense Force, which is battling against these "Mimics." On his first day of deployment, Keiji and his unit encounter "Mimics" and are all killed... Or was it all a dream? For some inexplicable reason, after every time he dies, he is resurrected and returned back to the day before the battle. Why does this happen to Keiji and how can he escape from this never ending cycle?
All You Need is Kill (Novel)
The story is told from the first person point of view of the protagonist Keiji Kiriya. Keiji is a new recruit in the United Defense Force, fighting against the mysterious creatures called 'Mimics' which have laid siege to Earth. Keiji is killed on his first sortie, but through some inexplicable phenomenon wakes up having returned to the day before the battle, only to find himself caught in a time loop as his death and resurrection repeats time and time again. Keiji's skills as a soldier grows as he passes through the time loops trying to change his fate.
- The Mimics resemble the Ing from Metroid Prime 2.