In addition, their eye color will change which can be seen when Naruto's eyes turn yellow with frog-like pupils. Like his son, Minato has the same features when using Sage Mode. When activating it ...

Naruto makes use of Mushi-ken, a game that has three hand signs representing a snake, a frog, and a slug. The snake will eat the frog, but the slug will dissolve the snake with its poison.