Crush Depth

Create: Deep Seas gave the ocean the power to crush your submarine. This gives it the power to crush you.

Crush Depth is an addon for Create: Deep Seas. It does not invent its own physics. It hooks into that mod's pressure model, the same depth math and the same hull ratings, and turns it on the player. When your hull starts creaking, you are already in trouble. When it breaches, the ocean finds you.

What it does

Depth-scaled crush damage. Exposed swimmers take it first. Sealed inside a hull that is past its rating, the crew still feels the squeeze, weaker than open water. A breach hits like swimming. It is gentle just past your limit and lethal in the deep, and it scales with world difficulty.

A diving-gear ladder worth climbing. Create's copper and netherite diving suits, Alex's Caves' diving suit, the Abyssal Adaptation enchantment (now on all four armour pieces: treasure and villager trade, never the enchanting table), and Curios like the Artifacts snorkel all push your unprotected limit deeper. Gear never touches hull integrity.

Assemble a complete suit and it pays off properly. A full diving suit grants a flat rated depth rather than the sum of its parts, and pieces mix freely between mods, because Create's suit has no leggings and other mods' do. Half a suit is half a suit. A whole one is a threshold.

The ocean goes dark the deeper you swim. Visibility falls away exponentially, colour drains toward black, and light fights back. A lantern in the deep is genuinely worth carrying, and lit structures resolve out of the murk as widening pockets instead of popping in at the fog line. Night Vision and Abyssal Adaptation help. It only ever removes visibility, never grants more than vanilla, so leaving it on is never a handicap.

Clearance. A single-level helmet enchantment that cuts straight through the depth fog. You will not craft it. It is treasure, the rarest thing in the mod, and it only turns up in chests.

Boyle's law air drain. Backtank air burns faster the deeper you breathe from a Create diving helmet.

The bends. Stay deep, then bolt for the surface, and you will pay for it: nausea, weakness, slowness. No hidden HP tax. Stand in Deep Seas' decompression chamber to recover. Sealed subs never build saturation.

Immersion. An actionbar depth gauge, hull creaks near crush depth, darkness and a low groan past 80% of your limit, and its own death message.

An advancement tab. Depth-relative goals that work in any world: Into the Deep, Crush Depth, Iron Lungs.

Plays well with others

Other mods' submarines protect you. Vehicles like Alex's Caves' submarine are opaque single entities with no hull to measure, so riding one is simply shelter. Add any modded vehicle to the list.

Re-rate blocks Deep Seas underestimates. Its automatic rating reads hardness, blast resistance and sound type, which makes a purpose-built deep-sea material from another mod look like ordinary stone. Name it in hullOverrides and it holds. Your Deep Seas config is never modified.

Fauna depth-locking. Stops deep-sea mobs from other mods (Naturalist, Unusual Fish, and similar) spawning at the surface where their own rules let them. Eggs, buckets and spawners are untouched.

Configurable to the last number

Tolerances, damage rates, difficulty scaling, every gear bonus, the full-suit value and which slots define one, advancement thresholds, the spawn list, hull overrides, sealed vehicles, and the entire fog model. Entries naming mods you don't have are simply never matched, so they cost nothing.

Vanilla-depth oceans are mostly safe on defaults. The mod wakes up when the world actually gets deep. Pair it with Deep Seas' deeperOceans, or a worldgen mod that digs, and the pressure starts to matter.

Requires: Create: Deep Seas, Create
Optional: Curios

Server-side logic. Install it on the client too for tooltips, fog and the localized death message. Un-modded clients can still join.