Marble Game

Inspired by Marble Game from Squid Game. 

The player and the opponent will get 10 marbles individually. The opponent will choose a certain amount of marbles it has, and the player has to guess whether the number is an even number or an odd number. If the player guesses correctly, the player takes away that amount of marbles from the opponent. If the player guesses incorrectly, the opponent takes away that amount of marbles from the player. First one to get 20 marbles wins.