The phrase refers to the final boss battle in Sally Face — Episode 4: The Trial , where Sal must use his guitar skills to destroy the "Endless One" and its protective barriers. Preparation & Required Items
: After the battle, pick up the knife in the white room. [S1E4] Fight Face
Guide :: Sally Face - Episode 4: Walkthrough and Achievements The phrase refers to the final boss battle
: Necessary for the "Her Fate" achievement. You must collect these before entering Room 103. The Boss Battle: Destroyer Walkthrough [S1E4] Fight Face
: Go to Room 103 to trigger the encounter. Guitar Mechanics : Press G to activate/deactivate the guitar.
: Completing the episode unlocks the "Suffer" achievement.