Sonic Advance series
Appearing at Ice Mountain Zone, Pen walks back and forth and when approached, makes a stop and launches snow balls at the player. The player has to avoid the snowballs it launches. It can be easily destroyed with a Spin Jump. Pen's appearance highly resembles Penguinator of Sonic the Hedgehog 3, but their methods of attack differ.
Sonic Advance 2
A newer model of Pen appears at Ice Paradise Zone in Sonic Advance 2 and actually behaves like Penguinator in the sense that, rather than launching a projectile, it will instead charge at the player. Unlike Penguinator, however, this version of Pen does not stand up at any point and resembles more of a penguin-shaped missile.