Just want to have a little fun thread. So by powerful, I mean it needs to be quite powerful like maybe around at superman's level or beyond to even God/omipotent. Basically it can be anyone that caught your eye and is very cable of beating the average superhuman. A few more rules are:
1. It can anyone or anything you can think off from aliens, robots, entity, witches just literally anything.
2. as basically mention in the title it can be from any source you've come across
3. add a little description of his/her/it power abilities are if its from if less popular source
4. Keep it non-comic book.
Bonus If you're into comic books, if you like you can think of an interesting versus match-up between your chosen character/s against a comic book character.
Man in black from LOST - can mimic and take the form of any individual, can manipulate people's dreams and manifest within them, invulnerable to explosions and immune to bullets. Can remember him killing a patrol of soldiers with ease.
Lucy from the 2014 movie Lucy - Basically she a omipotent at 100% brain capacity, I reckon she capable of beating superman at around 40% brain capacity