The story starts with the MC waking up in an unknown location. They, along with 99 other people. wake up only to find out that they are in a death game. The final prize is another chance at life and a wish. There is only 1 winner.
The participants have to go through 10 games. Each game is harder than the last. Starting easy, all the way to impossible. From a simple climb of a mountain that is infinite in height to a death battle over an active volcano with dragons flying overhead.
There is one saving grace. If not, the game won't be fun. The grace is that everyone has powers. The power depends on how you die and how far it is from your original death date. If you die from being cut and it is like 3 years before your original death, you can turn a body part of yours into a blade. But if it was like 20 years before your original death, anything you want will be cut.
The MC doesn't know how they died. Because of that, they can't use their full potential.
But in each game, they survive, and they awaken more and more. Somewhere near the endgame, the MC fully awakens their memories, but they don't tell anybody.
They make a very high IQ plan that is only revealed in the final game. As soon as the MC recovered their memories, they planned the rest of the games out, and they always went as they planned. They toyed with everyone, from their enemies, and allies, all the way to The Emperor of the place where the games are held.
After successfully winning, the MC is revealed to be one of the world's smartest humans alive, and they are evil, with them being the world's most wanted criminal throughout history. The way the MC died is one of history's most notable events that, even thousands of years in the future, people still talk about it.
Also, the reason the MC lost their memories at the start of the games, but not anyone else is because it is to balance the games out. Even with their memories lost, they still played lots of people like a fool without them even realizing it.
(The MC's power can be whatever you want. Same with a lot of other stuff. The plot holes can be filled out yourselves.)