How to reach the true final ending in Sonic Frontiers

Interestingly, Sonic Frontiers contains a true, secret ending that players can access through a rather simple method.

Sonic Frontiers: The Final Horizon, OT

Sonic Frontiers - True Final Boss Fight & Ending

Looks like the Final Horizon content is an option you're presented

Sonic Frontiers' Ending, Explained — Story Breakdown

Sonic Frontiers Secret Ending [Explained]

Sonic Frontier's Ending Makes a 'Sonic Boom' Character Canon

Sonic Frontiers - How to Unlock the The End True Final Boss Fight

Sonic Frontiers - All Bosses & Secret True Final Boss Fight + OST

Sonic Frontiers - Final Horizon DLC Spoilers Topic - Games - Sonic

What's Wrong with Sonic Frontiers: The Final Horizon?

How to Fight the True Final Boss of Sonic Frontiers

Sonic Frontiers' True Ending Explained