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Deltarune Chapter 4 secret boss guide

Deltarune hides numerous mysteries, yet the most rewarding are the secret bosses awaiting discovery. The Chapter 4 hidden boss remains elusive without a specific code, crucial for accessing Mike’s Room. Need the code to unlock this challenge? We’ve decoded it for you.

TV Building interior in Deltarune showing Mike's door

Locating Mike’s Room in Deltarune

This hidden area resides within Castle Town’s TV building. After entering the structure, seek out a labeled door requiring numerical input. Entrance demands solving the code puzzle first.

Code entry interface for Mike's Room

Access Code for Mike’s Chamber

Primary entry numbers are 6453, though alternate codes like 5962 may work depending on discovered phone digits. Codes vary per playthrough, requiring experimentation if initial attempts fail.

Mike’s Room Contents

Interactive cat statues dominate this space. One offers petting interactions, while another summons a spectral hand for retrieving distant items. A treasure chest and microphone-shaped crystal lead to additional challenges beyond the main chamber.

Defeating Motormouth Mike

This multi-phase battle requires mastering rhythm games and reflexes. Each stage presents unique mechanics:

Battle interface against Motormouth Mike

Audio Control Phase

Balance sound levels between extremes: maintain maximum volume during applause segments and silence during quiet intervals. Dodge falling microphones during neutral phases.

Feline Companion Round

Utilize the spectral hand to repeatedly stroke appearing cats, advancing to subsequent stages through persistent interaction.

Multi-Boss Showdown

Evade claw attacks while using the hand to collect kittens and reunite them with their guardian. Successful reunions trigger the final merged form.

Merged Mike confrontation

Final Confrontation

Persistent interaction with Merged Mike reveals the caretaker’s true nature through a concluding cutscene. The battle culminates in humorous revelations about Mike’s actual identity.

Post-Victory Unlockables

Success grants access to three challenge modes:

  • Pluey: Evade falling hazards while rescuing cats
  • Jongler: Precision throwing game targeting specific zones
  • Battat: Reflex-based strikes with color-coded bonuses

Post-boss minigame selection