Any interaction between Sara and Eggman, especially Sara's reaction to Eggman's plans to marry her.
When he appears, Metal Robotnik causes an explosion that sends Sonic and Tails flying backwards. Sonic lands on his feet while Tails lands on his head.
Sonic and Tails fighting Metal Robotnik by taunting it.
Sonic and Metal Sonic's battle-
Sonic: You might know everything I'm going to do...but that's not going to help you, since I KNOW EVERYTHING YOU'RE GOING TO DO! STRRRRRAAAAANGE, ISN'T IT?!
Particularly, when Sonic falls crotch-first on the nose of Robotnik's ship and starts writhing in pain. At the same time, Metal Sonic crashes through the bottom of Robotnik's ship, accidentally looks up Sara's dress, and receives a kicking from her for it-
Eggman: Oh no, how is that you're still alive, Sonic?! [Sonic ignores him and carries on writhing in evident pain] Huh? What's wrong with you, what are you doing? [Looks behind him]