Rig a Visual Novel
The explanation will be at the end.
The only way to win this is by suggesting a game that seems fair on the surface, but is secretly rigged in your favor from the outset. The following rules act against you and therefore mean you cannot involve a game with these elements:
- In a game of chance, the dice (or equivalent) fall how Death allows them to.
- If there are unequal roles in the game, Death must be allowed to choose beforehand which he would like to be. (White in Chess, Dealer in card game, etc.)
- Physically, there are no hard limits on Death's strength, speed, or form.
- Death will be the arbiter of any competition, if there is one.
- Death has a better poker face than anyone alive. And he's quite good at recognizing tics.
- The maximum number of opponents he will face in the same game at once is one.
This means games of physical prowess, team games, games of chance, games where either side could have an inherent advantage simply based on role, and games of face-to-face interaction are ALL excluded from the list of viable options. Since we can't expect a pity victory because "Death is too competitive to let anyone win," we have to assume any victory should come from convincing death that the game is fair when really the game was made so that it was rigged in your favor.
- Death has lived thousands of years and played thousands of players.
Then don't play him directly. The only way to play is indirectly.
- There can be no new information from the world of the living in Death's domain.
Then use what exists now for creating the game.
- Death would probably be among the brightest minds to have ever lived, if he ever lived.
- In the space of a minute, Death can experience a thousand minutes.
Then make sure the game is not a game that requires knowledge to win nor rapid mental processing. Make it so that he can't just think his way to the victory.
- Though Death allows the visitor to choose the game, he will reject games at his own discretion.
Make it seem perfectly balanced when in reality it's not. He has no reason to reject something he thinks is fair.
- Death must first understand the rules of the game before he will play that game.
Simple, the rules of a Visual Novel are as follows:
- Read the story
- When you get to a choice, select the best choice you can see
- Try not to get a "dead end" or "bad end"
- The winner is whoever gets the best ending of the game by the end of their first attempt at playing
There is no reason to refuse this. On the surface, it would seem fair. Both players are working with the same tool for the same end. In Death's mind, the game would be easy for him to win because he can use his immense knowledge and wisdom to determine all the right answers. He can get the best ending no problem.
The trick is, the player needs to make the Visual Novel. Say, "Give me the time to write a visual novel in this space separated from the flow of time. After I've written it, we both play the game. It will be a simple VN where the way to get to the ending is by selecting the right answers to the questions you're asked. At the end, the game will give both players a percentage score based on how well they do. Whoever has the higher score wins. If we tie, for example, if we both manage a 100%, it will be treated as your victory and my defeat. If I have lied to you about the rules, it will be treated as your victory and my defeat."
When writing the game include a "What's your name prompt" where if you give the name of your favorite fictional character, you will get an additional 5%. Make it so that by playing the game, you have to interact with multiple background elements that don't appear to be special and that even if you do so, no matter what you do on the first play-through, you can only ever get up to 95% best ending, based on the fact you would need to do a New Game+ in order to accomplish 100%. Because you would play using that character's name and the game is rigged to max out normally at 95% on the first play-through, Death will be tricked into thinking the odds are slanted in his favor, but really the odds are slanted in your favor. You're not cheating. The rules of the game are the same for both of you. You just happened to know how to slip an unfair advantage past him and never lied about the rules, meaning he can't claim that you cheated because it was all within what was allowable.
I will accept an 'answer' to this question if the victim can have at least a 35% chance of beating the Death, assuming Death is true to form.
You either get a higher score than Death or you don't. 50% chance either way, since you already know everything about the game. Since you know the extra 5% trick, your odds are actually increased. Even if Death does everything after the name right, your odds of winning are much higher than 35%. This just requires that death does not reject your proposition, which you rigged things in his favor (on paper) so that he has no reason to reject the game.
This, as an answer, is honestly "cheezing" the system big time, though. In reality, there is no way an actual "good" answer can be made because Death will reject anything he doesn't think he has the obvious advantage in.