As soon as the simulation starts, the standard Undertale UI (Mercy, Act, Item, Fight) shatters. Your only option is to survive. Omega Flowey’s face fills the screen. The attacks here are relentless but slow:
Pro Tip: Do not try to "Fight" back yet. You have no weapons. Focus entirely on dodging. The goal of Phase 1 is to survive for approximately 45 seconds until the first Soul appears. Omega Flowey Fight Simulator
Glitches & Incomplete Phases – Many browser-based simulators crash during the “SOUL steals the human SOULs” segment. I’ve also seen hitboxes misalign, the “SAVE” healing phase fail to trigger, and Flowey’s laughter loop indefinitely. As soon as the simulation starts, the standard
No Emotional Payoff – The original fight works because of the narrative lead-up and the six SOULs rebelling. Here, it’s just a mechanics demo. Without the story weight, it feels hollow after the third attempt. Pro Tip: Do not try to "Fight" back yet
Because "Omega Flowey Fight Simulator" is a high-volume search term, it is a prime target for malicious actors.
The Omega Flowey Fight Simulator is a browser-based or downloadable fan game that recreates the chaotic, multi-phase battle against Omega Flowey from Undertale. It focuses on replicating the bullet hell patterns, soul modes, and dramatic phase changes of the original fight, often adding new challenges or mechanics.
These simulators are popular among Undertale fans who want to practice the fight, experience it with altered difficulty, or enjoy the spectacle without replaying the entire game.