Biomes

The world of Planet Zezura contains both underwater and surface environments. The planet is described as having "harsh, desert-like conditions" on the surface, suggesting possible land-based areas alongside the underwater zones. A partial list of biome names was spotted in file names during Dev Vlog #2 (about world building). These names may change before or during Early Access. The game is built on Unreal Engine 5 which enables more detailed, larger-scale biomes with improved lighting and creature density compared to the Unity engine used in previous games.

Dynamic Weather

Dev Vlog #1 (April 23, 2025) showed early footage of a dynamic weather system that will affect underwater conditions. This is a franchise first; previous Subnautica games had static weather conditions. Storms and shifting currents can change how biomes look and feel over time, altering visibility and potentially redirecting fauna movement patterns.

Depth-Based Progression

Unlike the original Subnautica, where players began at the surface and gradually pushed deeper, Subnautica 2 starts players deep underwater. After a ship crash, players are propelled toward the surface, meaning the opening experience reverses the traditional progression. Playtest impressions describe this as "fear-inducing" since players are immediately surrounded by the unknown rather than easing in from a safe, shallow starting zone.

The gene modification system also ties into biome access. Players can use the Biosampler to collect genetic material from creatures, then adapt their own body for survival in hostile environments. Abilities like enhanced night vision, faster swimming, and camouflage allow players to survive in biomes that would otherwise be inaccessible, adding a biological layer to depth progression alongside vehicle depth upgrades.

Environmental Hazards

The reveal trailer showed environmental hazards beyond hostile fauna. A powerful water vortex was shown dragging a player into an abyssal cavern, suggesting that underwater currents can physically move players and may serve as both obstacles and shortcuts between biomes. Combined with the dynamic weather system, biomes may present different hazard levels depending on conditions.

Confirmed Biomes

Start Zone

The initial area where players begin after the opening sequence. Unlike the first Subnautica's Safe Shallows, Subnautica 2 reportedly starts players deeper underwater after a ship crash, then propels them toward the surface. The Start Zone may be the area players reach after this sequence. Given the reversed progression, the Start Zone likely contains essential early-game resources and relatively low threat levels to allow players to orient themselves.

Kelp Forest

A returning biome name from the original Subnautica. In the first game, the Kelp Forest was one of the most recognizable environments, with towering creepvine plants reaching from the seafloor toward the surface. Creepvines provided fiber and seeds, and the biome was home to Stalkers. Its return on Zezura was well received by the community, though the specific flora and fauna in the Subnautica 2 version will be native to Zezura rather than recycled from Planet 4546B.

Coral Gardens

A biome with extensive coral formations. File names spotted during the vlog may indicate sub-biomes within this area (though their exact grouping is unconfirmed), including Dolerite Spires and Graveyard Spires. Dolerite is a real volcanic rock type, suggesting the Dolerite Spires sub-biome may feature dark, volcanic rock columns covered in coral growth. The Graveyard Spires name implies skeletal or decayed formations, possibly the remains of massive dead organisms or ancient structures. The original Subnautica had the Grand Reef with coral features, but this appears to be a distinct environment.

Sparse Plains

An open, relatively barren biome with limited cover. This is the confirmed habitat of the Collector Leviathan, which spawns approximately 20,000 to 25,000 units from the player upon entry. The openness of the terrain means very limited cover from the Collector's line of sight, making this one of the most dangerous biomes to traverse. Players need to rely on flares for distraction and sound/light discipline to avoid detection.

Jelly Plateaus

A biome likely featuring jellyfish-related formations or fauna on plateau-style terrain. The original Subnautica had the Jellyshroom Cave, a bioluminescent underground biome populated by large jellyfish-mushroom hybrids. The Jelly Plateaus appear to be a separate take on a similar theme, set on open plateaus rather than in a cave system.

Overgrown Ruins

One of the most intriguing biome names. The community has speculated about what the ruins represent: remnants of Architect (Precursor) structures, old human installations, or something entirely new to Zezura. The "overgrown" descriptor implies structures reclaimed by local plant life over a long period, which could provide both unique resources and story-relevant scanning opportunities. In the original Subnautica, Precursor facilities were scattered across biomes rather than forming their own; a dedicated biome built around ruins would be a significant departure.

World Tree

A biome suggesting a massive biological structure forming the basis of an entire ecosystem. No official details have been shared, but the name implies a single enormous organism (like a colossal tree or coral formation) that defines the zone's ecology. If the name is literal, this could be one of the largest single organisms players encounter in the franchise.

VepZone

A biome with no publicly available details beyond its internal file name. The unusual naming convention (camelCase with a capitalized "Z") may indicate a placeholder or internal designation. See the dedicated VepZone article for community speculation.

Void

In the original Subnautica, the Void (also called the Dead Zone or Crater Edge) was the open ocean beyond the playable area, populated by Ghost Leviathans that attacked anyone who ventured too far. Its return suggests a similar boundary mechanic keeping players within the intended map area, though the specific deterrent creatures on Zezura have not been revealed.

Biome Summary

Discovery of biome names

The names of several biomes were first spotted by a Reddit user who noticed file names visible in the background of a dev vlog video produced by Unknown Worlds Entertainment. The file names appeared on a developer's screen during the vlog and contained references to specific biome areas. This accidental leak gave the community its first look at the scope and variety of Zezura's environments.

Note: These biome names were extracted from development file names and may not represent final naming. Some names may change before or during Early Access, and additional biomes are expected to be added over the course of development.

Handcrafted design

Like the original Subnautica, the biomes of Planet Zezura are entirely handcrafted rather than procedurally generated. Every terrain feature, resource placement, and creature spawn point is deliberately placed by the development team. This approach allows for tightly designed exploration paths, deliberate pacing, and carefully staged moments of discovery and surprise.

The Unreal Engine 5 technology used for Subnautica 2 enables several custom environment tools that support this handcrafted approach:

• MeshBlend: A custom tool developed for seamless mesh blending, allowing different terrain types and biome borders to transition smoothly without visible seams.

• Tufa Kit pipeline: A specialized pipeline for creating rock formations. Named after tufa, a type of limestone formed by mineral precipitation, this tool allows artists to rapidly create varied and natural-looking rock structures across different biomes.

These tools were discussed in the Dev Vlogs, where environment artists demonstrated how they build and iterate on biome geometry.

Biome-specific resources and creatures

Following the design pattern of the original Subnautica, each biome on Zezura is expected to have its own set of unique resources, creature species, and environmental hazards. This biome-specific distribution drives the exploration loop by requiring players to venture into new and more dangerous areas to gather materials needed for advanced crafting.

Creatures like the Collector Leviathan (Sparse Plains), Hammerhead, and Waterslug are among the known fauna that populate these environments, though the complete creature roster and biome assignments for most species have not been confirmed.

Early Access expansion

According to the Early Access roadmap, the initial launch will include several biomes with more to be added through post-launch updates during the Early Access period. Anthony Gallegos stated that players will "be there when we first add new vehicles, craftables, biomes, and leviathans," confirming that biome additions are a planned part of the ongoing development cycle.

Cut Biomes

Leaked milestone documents (confirmed authentic by KRAFTON) indicate two biomes were cut from the Early Access scope between Q2 2023 and Q2 2025. The specific biomes that were removed have not been named publicly. They are expected to be added during the 2 to 3 year Early Access development period.

Differences from Previous Subnautica Games