Each player has 10 balls. Both players take several stones in their hand, squeeze it, and then stretch it forward. The player who owns the right to move must guess the odd or even number of stones in the hand of the second player. If he guesses correctly, then he takes from the second player as many stones as he holds in his hand. And vice versa.
Try playing it sometime with a friend or even your mom.
If there is no opponent, this application will help out