Robotnik's buttocks can be seen on some episodes.

Women wear skintight outfits that reveal their breast.

lots of severe innuendos.

Cartoony violence like kicking, smashing, spindashing etc, In one episode Sonic uses a Sword to fight Robotnik, explosions in some episodes

Sonic and Robotnik insult each other regularly

In the Sonic Sez segments, there is one about smoking and one about drinking alcohol, which causes Scratch and Grounder to get drunk.

Scenes acceptable for a series classified TV-Y.