Sometimes the game is played such that a missed shot requires the player to start over at the first position.

The game requires the player to use both modes of play.

It required the player to act before an enemy attacks.

Should the hero lose all their health, the game is over, requiring the player to start again.

It may start to change next June, when the rule requiring players to be 19 and a year removed from high school takes effect.

Each mission requires the player to kill a certain number of the enemy.

They can also present further plot points without requiring the player to take a break by watching a cut scene.

They required players to plan each move and anticipate the opponents' moves ahead of time.

He too could play a 7, requiring the next player to draw 6, etc.

A typical mission requires the player to operate on a patient.