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The main mode

Infect Game Mode

Infect a host and fight organ by organ from the nose to the brain. Infect Game Mode is the only one that earns XP and adds generations to your virus's lineage, and how far you get here opens the rest of the game.

The title screen, with Continue, New Game and Load Game
The title screen, with Continue, New Game and Load Game
On this page13
  1. Infect a Host
  2. Choose your point of entry
  3. Head Start draft
  4. INFECTED! Landing on a host
  5. Welcome to a new organ
  6. Leaving an organ
  7. Pause menu
  8. Abandon run
  9. Run summary: results
  10. Run summary: gear found
  11. Your next generation
  12. Total Infection
  13. Your special buttons

Infect a Host

Main mode

The big green button on the main menu: infect a host and push through its organs, one boss at a time. It is the only Game Mode that earns XP and makes generations.

  • Main menu button tagged “Collect: XP”
  • XP per run: 1 per 3 kills, 8 per room cleared, 150 for a victory
  • 8 organs in order: Nasal Passage, Lungs, Bloodstream, Lymph Node, Gut, Liver, Bone Marrow, Brain
  • Each finished run becomes one generation of your lineage
  • A victory means beating the Brain's boss: the host is fully infected
  • Loaded run modifiers are used up by the run (as in every Game Mode)
From the Codex

Each infected cell releases new virions that go on to infect its neighbours, so an infection can grow exponentially.

Fun fact: A single flu-infected cell can release thousands of new virions within hours.

Viral Spread in the Codex

Once your lineage has reached deeper organs, a run can start in any organ it has reached instead of the nose.

  • Opens with the “Start in deeper areas” milestone (Level 3 · Gen 2)
  • Shows Areas 1–8: reached ones show their organ and boss, the rest read “Not reached yet”
  • Area 1 (Nasal Passage) is the normal start
  • Backing out costs nothing: modifiers are only used once the run starts
From the Codex

Beginning a run in an organ you've already reached.

Fun fact: Starting deeper is faster, but you miss the earlier organs' loot and traits.

Starting Deeper in the Codex

Head Start draft

Deeper starts

Starting past the first organ opens a draft to make up for the organs you skipped: pick 6 traits from a pool of 20.

  • Always 6 picks from 20, however deep you start
  • The same trait can show up twice; picking both stacks it
  • Deeper starts roll rarer traits
  • “Pick for me” fills your picks (rarer traits and synergies first); once full it becomes “Re-roll”
  • Cards flag the SYNERGY a trait would complete with what you hold
  • Pandemic Game Mode runs get the same draft, matched to your deepest organ
From the Codex

Beginning a run in an organ you've already reached.

Fun fact: Starting deeper is faster, but you miss the earlier organs' loot and traits.

Starting Deeper in the Codex

Every run opens on an “INFECTED” title that slams in over a green pulse while the game picks the host you've infected.

  • Hosts are usually people; about 1 run in 5 lands on an animal instead
  • Infecting an animal adds it to the Codex
  • Once host traits are introduced, a reveal card shows your host and its traits before the run begins
  • In Pandemic Game Mode the hosts are locals with names from that city, and the animals are the city's own wildlife
From the Codex

The person or animal you infect at the start of a run.

Fun fact: Rarer hosts have bigger effects and pay more nucleotides.

Hosts & Host Traits in the Codex

The first time any of your viruses reaches an organ, a welcome card lists everything it unlocked.

  • Which new gear tier can now drop
  • How far gear combining now reaches
  • Which named set that organ's boss drops
  • A new starting point: future runs can begin there with a 6-trait head start
From the Codex

The organs of breathing, where oxygen enters the blood and carbon dioxide leaves it.

Fun fact: Spread flat, the surface of the lungs' air sacs would cover roughly half a tennis court.

Lungs in the Codex

Before you descend, the game asks you to confirm, because there's no coming back.

  • Counts how many rooms are still unexplored
  • Warns that anything left on the floor is lost
  • Warns when a tumor is still alive: it will metastasize to the next organ at its current stage
  • Choose Stay or Move on
From the Codex

Viruses spread between organs through airways, blood and lymph: flu can move from the nose down into the lungs, and HIV travels through the blood to lymph nodes.

Fun fact: Inhaled droplets small enough can bypass the nose entirely and land deep in the lungs.

Drop Shaft in the Codex

Pause menu

Run · Settings

Pausing fills the screen, with the run blurred behind it. On iPhone it has two tabs, Run (everything about the run you're in) and Settings; on iPad and Mac the two sit side by side.

  • Status strip: organ, kills, extra lives, your host's name and age, and any host condition
  • Traits: every trait taken, with stacks, plus a Synergies tab
  • Stats: every stat for this run and where it comes from, with the traits you've picked up
  • Resources: nucleotides, materials, RNA, modifiers found and gear found this run
  • Modifiers: what's loaded, each upside and drawback, and any combo
  • New this run: the briefing card of every first encounter
  • Challenges: daily, weekly and milestone progress (collect rewards from the main menu)
  • This room: its tier and every boon and drawback it carries
  • Settings: sound, vibration, language, controller and keyboard, gameplay data and links, without leaving the run
  • All its tiles and settings fit without scrolling

Abandon run

Clean slate

You can quit a run from the pause menu at any time, and everything goes back to how it was before the run started.

  • “Your virus is cleared and everything goes back to how it was before this run: nucleotides, gear, materials, RNA, XP and modifiers.”
  • Abandoning doesn't end a generation: it plays again next run with the same mutation
  • No new mutation is chosen after an abandoned run

The first page of every run's summary: how it went and what it earned.

  • HOST INFECTED, or how your virus died
  • Rooms cleared (sets survived in Endless Game Mode)
  • Adenine, Thymine, Cytosine and Guanine collected
  • New Codex entries discovered
  • Materials and gear found, with the best piece's level and rarity
  • XP gained, your virus's new level and any skill points
  • Your generation's permanent legacy bonus and its kill count
From the Codex

The building block of DNA and RNA: a sugar, a phosphate and a base (A, T, C, G in DNA; A, U, C, G in RNA).

Fun fact: Influenza stores its genes as RNA, so it uses U in place of T.

Nucleotide in the Codex

Every piece of gear the run found, ready to compare, equip or dismantle on the spot.

  • Sorted by rarity and level
  • Tap a piece for its stats, abilities, uniques and set
  • Compared with what you wear in that slot: stronger, weaker or an empty slot
  • Equip straight from the summary
  • Pick pieces (or Pick all) and dismantle them for nucleotides
From the Codex

The protein shell that encloses a virus's genome, built from repeating subunits called capsomeres. Most are icosahedral (20 triangular faces) or helical.

Fun fact: Capsids self-assemble: the proteins snap together on their own, like a puzzle that builds itself.

Capsid in the Codex

After a finished Infect run you choose the mutation your next generation is born with.

  • Choose 1 of 3 strains (1 of 4 with a second virus): boons, curses or a mix
  • Picking the same strain again stacks it (“INHERITED ×N · AMPLIFIED”) and shows what it was before
  • Some mutations turn the lineage into another virus
  • Pandemic and Endless Game Mode runs skip this page
From the Codex

Gene duplication gives a virus a spare copy of a gene that can take on a new job.

Twin Genome in the Codex

Beat the Brain in Infect Game Mode and the ending plays: every organ lights up in turn along a spreading line of infection.

  • The 8 organs light up one by one
  • “TOTAL INFECTION · You have fully infected the host”
  • “The immune system has nothing left to send. The host is yours.”
  • Stats: organs taken (8/8), rooms cleared, cells destroyed
  • Continue leads to the usual run summary
From the Codex

Protected by the blood-brain barrier, the brain has its own immune system run mostly by microglia and astrocytes.

Fun fact: The brain has around 86 billion neurons and roughly as many glial cells supporting them.

Brain in the Codex

On a new save the special buttons arrive one at a time, so there's less to learn at once.

  • Shift (your signature ability) appears after your first finished run
  • The Ultimate appears after your second
  • A notice points out each new button the first time
From the Codex

Your three special buttons on the right.

Fun fact: Save the ultimate for bosses and big waves.

Signature, Ultimate & Skill in the Codex

See also