DEEPHOLD

3,900 meters down, Meridian Trench Rig should not exist on any chart — and the abyss below it has started sending things up.

You are the new night chief. Between waves, route power, harvest thermal vents, and bolt six turret families to the rig's hull. During the siege, you don't aim a single gun — you manage: trigger turret Overcharges, reroute power between hull sectors, detonate pre-placed mines. And every wave, the trench adapts: an AI director mutates enemy composition — resistances, speeds, siege behavior — based on how well your defense is holding. Your marine biologist reads each mutation aloud, so the game telegraphs its own evolution and you answer it.

But the creatures aren't attacking. They're fleeing. The deeper the pressure goes, the clearer the pattern becomes — and your crew is splitting over what to do about it. Thirty waves. Three bosses. Three endings.

What's here:

- 6 tower families x 3-tier upgrade trees — no single build survives every seed

- Adaptive AI director: the trench mutates in response to YOUR defense

- The trench economy: spend thermal cells, harvest vents, or bank into the Pressure Core for global buffs

- Fully seeded procedural runs — same seed, same trench. Share seeds, race friends.

- A full story spine: branching dialogue, an allegiance choice at wave 25, boss encounters read through live sonar

- Narrated story beats — voiced by the crew at every key moment (45 clips, toggleable in Settings)

- Signature abyssal presentation: bioluminescent trails, pressure-wave rings, sonar sweeps, depth fog

- Original WebAudio deep-sea soundscape (synthesized, zero assets)

- Endless mode unlocks after the campaign

A full 30-wave campaign takes most players 75-100 minutes; endless mode and 3 endings push it well past that.

Made with vanilla HTML5 + JavaScript. Original code-drawn art. Every sound synthesized fresh for this game.

VN

Controls — Move survey cursor: WASD / Arrow keys. Select/confirm: Space. Quick turret select: 1-6. Overcharge: O. Upgrade: U. Targeting: T. Sector overdrive: Q/C/E. Power surge: G. Launch wave: S. Bank cells: B. Sell: X. Mine: I. Harvest: V. Buffs: 7/8/9. Mutation report: Tab. Mute: M. Pause: Esc. Touch: on-screen d-pad + action button, or tap pads/vents/mines directly. Narration toggle, text speed, screen shake, and mute in Settings.