[ Submarines ]
Submarines are the key to RELL Seas' deepest content. While surface ships rule the open ocean, the true treasures of the world lie in the deep - hidden caves, underwater dungeons, rare sea creatures, and sea regions inaccessible any other way. The submarine is not just a vehicle; it's a progression gate that opens up an entirely different layer of the game.
Controls
Depth layers· 7 confirmed
Pressure system
Pressure is the primary environmental threat in deep-sea exploration. As you descend, the water pressure increases. Without the proper submarine armor equipped, your character begins taking damage on a timed interval - and the deeper you go, the faster that interval ticks.
Water currents
Every depth level has its own directional current. These currents are inspired by One Piece's Grand Line - the real lore features one giant ocean current that influences all sea travel. RELL Seas gives each depth its own current to reward navigation knowledge.
[WILDLIFE FLOW] · Wildlife naturally follows the current of its depth layer. Fish swim with the current, not against it - you can use this to predict creature movement.
Underwater wildlife & content
- Surface fish (standard species) → Piranha-type fish at depth 4+
- Giant surface fish → Whales and Eels at depth 4+
- Standard sea creatures → Aggressive apex predators at depth 6+
- Leviathans: the largest and most dangerous creatures, found in the deepest depths
- Hidden cave entrances (found by following depth currents)
- Underwater dungeons (multiple rooms, escalating enemies)
- Mini-boss encounters (dangerous, high-reward creatures)
- Full boss fights (rare, deep-depth exclusive encounters)
- Unique material nodes (underwater-only crafting resources)
Oxygen & underwater physics
Players do not have a fixed oxygen timer that counts down to death. Instead, oxygen bubbles spawn randomly around the player as they swim. The deeper you go, the rarer these bubbles become - meaning extended exploration at great depths becomes genuinely dangerous.
DEPTH RISK · At extreme depths, oxygen becomes so scarce that without submarine armor, survival is measured in seconds rather than minutes.
- Walk speed is reduced while swimming/moving underwater
- M1 attack animations remain the same speed as on land - combat parity is maintained
- Dashing becomes directional when looking up or down - you move toward your camera angle
- Animations have a slow, floaty quality that adds to the underwater atmosphere
- All sound effects gain a distorted underwater filter
GRAVITY · Gravity behaves differently underwater - movement has a slow, weightless quality that affects how you navigate and fight.
Confirmed notes
- Submarines were showcased in Movie 2 and Movie 3 of the RELL Seas developer showcase series.
- The Sub Cola item is a direct One Piece reference - the cola-powered submarine from the Franky arc.
- Submarine armor must be a COMPLETE set - confirmed directly in Movie 3. Partial sets provide no pressure protection.
- Water currents per depth were designed to mirror the Grand Line ocean current concept from One Piece.
- Leviathan battles are a confirmed submarine combat scenario - giant sea creatures exclusive to submarine encounters.
Frequently asked questions
How do you get a submarine in RELL Seas?
Submarines are summoned with the Sub Cola item. The item is tied to progression and is not described as a starting unlock. The exact milestone or acquisition route remains unpublished, so the wiki does not assign a level or price.
What are the submarine controls?
Exploration controls use movement, turning, ascent, descent, engine, battle-mode, and sonar inputs. Battle Mode changes aiming and adds weapon controls. The complete key table on this page separates exploration from combat so the two control states are not mixed.
How does water pressure work?
Deeper layers apply increasing pressure and require complete protection appropriate to the depth. Partial armor sets are not documented as sufficient. Exact damage thresholds and final gear requirements should be treated as pending until release data confirms them.
What can you find underwater?
Documented underwater content includes hidden cave entrances, dungeons, sea creatures, bosses, and material nodes. Some deeper content is associated with later sea regions, while exact locations, rewards, spawn conditions, and access gates remain unpublished.
