Bad Time Simulator

Bad Time Simulator is a fan-made browser game inspired by one of the most iconic boss battles in Undertale. Instead of recreating the entire RPG, the game focuses entirely on the unforgettable fight against Sans, challenging players to survive relentless waves of attacks using quick reflexes and precise movement.

Whether you're an Undertale fan or simply enjoy bullet-hell games, the game offers an intense test of skill that can be played instantly in your web browser.

BAD TIME SIMULATOR - SURVIVE THE LEGENDARY SANS BOSS FIGHT

In Bad Time Simulator, you control your SOUL, represented by a small heart, and must dodge countless attacks launched by Sans throughout the battle.

As the fight progresses, attack patterns become faster and more complex, requiring players to memorize movements, react quickly, and remain calm under pressure. Every mistake costs valuable health, making each successful dodge feel incredibly rewarding.

Multiple Game Modes for Every Skill Level

• Normal Mode recreates the complete Sans battle from Undertale.
• Practice Mode allows unlimited training against repeating attack patterns.
• Endless Mode tests your endurance with increasingly difficult waves.
• Single Attack Mode lets you practice one specific attack at a time.
• Custom Attack Mode supports community-created attack patterns and custom challenges.

Learn to Survive Sans' Signature Attacks

• Bone attacks that appear from multiple directions.
• Blue Bones that require careful movement.
• Orange Bones that encourage continuous motion.
• Powerful Gaster Blaster laser beams.
• Blue Soul gravity sections that completely change movement mechanics.
• Fast combinations of bones and lasers that demand precise timing.

Simple Controls, Incredible Challenge

• Arrow Keys or WASD – Move your SOUL.
• Z or Enter – Confirm selections.
• X or Esc – Cancel or return to menus.
• M – Mute or unmute the music in supported versions.

Tips to Improve Your Performance

• Practice difficult patterns individually before attempting the full battle.
• Focus on small, controlled movements instead of constantly moving.
• Memorize recurring attack sequences to improve your reaction time.
• Stay calm during Blue Soul sections where gravity changes your movement.
• Challenge yourself in Endless Mode after mastering the main battle.

SIMILAR BULLET HELL GAMES

• The Glitched Attraction
• Backrooms Hotel: Lost Floor
• Train 8: Anomalous Route

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