The hardest bosses to defeat in Undertale

Ranking based on votes from the community

1. 

   1

   Sans

   3 votes

   - The most feared boss in the game. - Extremely fast attacks, with unfair mechanics. - A true test of patience.

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2. 

   2

   Undyne the Undying

   1 votes

   A brutal version of Undyne with lightning-fast attacks, requiring perfect reflexes and memorizing arrows in all directions. She's a wall for many players.

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3. 

   3

   Mettaton Neo

   1 votes

   • Now you can have a real fight with Mettaton NEO

     (+1)

   Mettaton Neo represents a formidable challenge due to its devastating attack power and the need for precise strategy to defeat. Its high defense and rapid attacks require the player to be attentive and react optimally to survive and find an opening.

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5. 

   4

   Omega Flowey

   0 votes

   Insane first boss, screen full of glitches, random weapons, and attacks that are impossible to predict on the first try.

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6. 

   5

   Asriel Dreemurr

   0 votes

   • Complex and challenging combat phases

     (+4)

   Asriel Dreemurr represents the pinnacle of difficulty in Undertale, presenting a multi-phase challenge that demands exceptional endurance and pattern memorization. His transition through various forms, each with increasingly complex and devastating attacks, pushes the player's skill to its limit.

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