69%Strong matchSonar Shock
82%21082% positive reviews, Very Positive across 210 reviews·FPS · RPG
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SU is a 2.5D deduction puzzle game. The submarine Nautilus suffers a mechanical failure during its voyage. Dr. Pierre investigates and finds anomalies in every area. Explore the deep blue depths, follow Dr. Pierre as he unravels the secrets of the Nautilus.
During its voyage, the submarine suddenly experienced a mechanical failure. Dr. Pierre hurriedly began investigating, only to find abnormal intrusions in every area.
Investigate cases in the azure abyss, and follow Dr. Pierre to uncover the secrets of the Nautilus.

Immerse yourself in the eerie atmosphere of the Nautilus, filled with secrets and unsettling anomalies.


Experience 2.5D deduction + puzzle gameplay, combine your observation skills to solve problems and navigate through various cabins.


Many anomalies are hidden in the submarine, related to the time vortex. Can you unlock the secrets of time and space and escape the submarine?


1866
Dr. Pierre, the owner of the Nautilus, and his seven sailors accidentally salvaged a "compass" during their voyage.
This compass allowed him to glimpse his true position in the universe. It also caused the Nautilus to sink into a time vortex.

2998
"Su" is a student from a future city. During an underwater trip, she encountered an ancient submarine trapped in time and space.
Su entered the submarine to explore but was captured by the time vortex into another unknown space-time.
Players play as Dr. Pierre.
Interacting with items marked with time stamps can penetrate time to obtain more clues.
Explore interesting "time wormholes" and various props to uncover the truth of the story.
Steam data © 2026 Valve Corporation. Trademarks are property of their respective owners.
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The best games like Abnormal1999:SU - Unlocking the 4th Dimension are Sonar Shock, Subnautica, SCP: Secret Files, Mind Diver, and Submachine: Legacy.
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