Restart, Restart Trophy in ICEY

Immediately after Pitfalls, you will drop into a ravine and the Narrator gives you a treasure chest as a 'reward' for not obeying. Destroy this, and you will be prompted to proceed to the right - don't. Instead, go back to the left to get into a bonus area which leads to a dead end. Idle here for the trophy and the first optional ending in the game, as shown in this video.