One room. One hundred waves.

There is no map and nowhere to fall back to. Chamber 7-A is a single reinforced floor, and everything that happens to you happens on it. The only thing that changes across a run is what you have become.

• 100 waves across 10 levels — a full run is 35 to 50 minutes
  
• Waves are generated rather than scripted: the same rules, a different fight
  
• A run can be suspended and resumed, but never checkpointed. Death ends it

The build is the game.

An upgrade every three waves, an experimental Protocol every ten. Almost nothing is a flat damage increase — the numbers that matter come out of what stacks into what.

• 62 upgrades and 13 Protocols that combine rather than add
  
• Ricochets that split on every bounce. Lightning that conducts through frozen targets
  
• Echoes of yourself that keep firing your weapon after you have moved on

It escalates on eleven axes, and health is the smallest of them.

Enemy health barely triples across a hundred waves. What changes is how many arrive, how fast, from where, and how much of the floor is trying to kill you.

• 4 enemy archetypes, promoted to Elite and Prime ranks as the run goes on
  
• The chamber itself turns against you: the floor is not neutral by level 9
  
• Difficulty you can out-build is difficulty worth having

THE OVERSEER is at wave 100.

It is the reason the chamber exists, and it has been watching the whole run. Past it the Overload cycles begin, and they do not stop.

• A multi-phase fight against everything the facility learned about you
  
• Endless Overload cycles after it falls, for anyone who wants the number to keep going
  
• 32 achievements, most of them for the things you did not have to do

Everything you see is generated.

No image files, no audio files. Every shape, sound and note in this game is produced by code at run time — which is why it starts in under two seconds and fits in a hundred megabytes.

• Keyboard, mouse and gamepad, fully remappable, with on-screen prompts that follow the device in your hands
  
• Auto aim, adjustable screen shake and flashes, high-contrast mode — playable on a keyboard alone
  
• 20 languages