At this point in the franchise's life, Sonic the Hedgehog games star Sonic's friends as much as the titular hedgehog himself. A Sonic game wouldn't feel complete without Knuckles, Tails, and Amy playing some part in the story. That's why Sonic Frontiers will almost certainly have them influence the story in one way or another. Their names may not be part of the franchise's title, but Sonic's friends are Sonic the Hedgehog mascots nonetheless. Even so, it's hard to say what role they'll play in Sonic Frontiers since Sonic Team and Sega have released only limited details on the game so far.