Imawa no Kuni no Alice, Dead Tube Recommendations
Each of them reminded me of the other, because in each series there are challenges/games that people have to take part in/can take part in. In Dead tube, there is a reward with money if you win and a huge punishment if you lose. In Imawa no Kuni no Alice, people have to take part in games to survive, and you have a chance of dying in games. Some games are easier that others.