Skills, lab and challenges
Level Up
Every run feeds your lineage. Earn XP and levels, spend points across a three-branch skill tree, upgrade the Petri Lab, load run modifiers and chase hundreds of challenges, while new mechanics arrive one level at a time.
XP and levels
Level up your whole lineage
Every finished Infect Game Mode run pays XP for the cells you destroy and the rooms you clear, plus a big bonus when the host falls. Challenges add more XP when you collect them. Levels come quickly at first and then get steeper, and each one hands you skill points for the tree. Your whole lineage shares one level, one skill tree, one Petri Lab and one gear bag, so switching virus never costs you progress.
- Infect only: Pandemic Game Mode and Endless Game Mode runs give no XP and make no generations.
- Generations: Each finished Infect Game Mode run adds one, and longer lineages open deeper unlocks.
- No cap: There's no level cap, and the skill points each level pays step up as you climb.
- Bonus points: Milestones for beating organ bosses and reaching new organs pay extra skill points.
- Respec: Refund every skill point for RNA, then rebuild your tree any way you like.
Skill tree
Three trees, three ways to grow
Spend skill points across three trees: Replication to hit harder and faster, Transmission for speed, stealth and ambushes, and Persistence for health, healing and comebacks. Each tree has three columns, its own resource (Viral Load, Momentum or the Reservoir), an active skill whose augments change how it works, and three capstones to choose from. A row opens once you've spent enough points in that tree, and then every skill in it is open.
- Rows by points: 5 points in a tree opens its second row, then 8, 11, 14 and 17; the capstones need 21.
- Skill shapes: Circles are stats, rounded squares are conditional, diamonds are the tree's resource, octagons are active skills, hexagons are augments and crests are capstones.
- Active skills: One per tree, equipped one at a time for the SKILL button, while resources and stacking skills show as clock icons under your health.
- Viral Genome: A gear piece that adds skill levels, even past a skill's maximum.
- Stats screen: See where every stat comes from, and your total play time, from the main menu or pause menu.
Capstones
Capstones that change how you play
Each tree ends in three capstones, one under each column, and you can own only one per tree. They open at 21 points in the tree and do more than raise stats: Pandemic Spark arcs your critical hits to nearby cells, Pandemic Front turns Aerosolize into a sweeping wall, and Undying Strain gives you a few seconds to kill your way back from the brink.
At a glance
- Pick one: Owning a capstone blocks the other two in that tree; switching is free.
- Late opening: Capstone rows also need a long lineage and the Brain reached.
- Genome capstones: A Viral Genome can carry a capstone, standing in for yours while it's worn.
Petri Lab
Grow stronger between runs
Spend the nucleotides you collect on permanent upgrades that carry into every run, across three sections: Core Genome, Signature Ability and Ultimate. Core upgrades and your ultimate's reach and charge help every virus, while the rest belong to one virus and only count while your lineage is that virus. Most upgrades unlock a milestone effect every few levels, and rare RNA from Pandemic Game Mode opens the advanced ones.
- Bonus levels: Past their base levels, most upgrades keep climbing at a gentler rate.
- Hidden mastery: Reach the top of what's shown and secret mastery tiers appear, milestones and all.
- Milestones: Effects like a shield that blocks the first hit in each room switch on by themselves.
- RNA: It unlocks the advanced upgrades, and every few levels of an upgrade ask for some too.
- Four bases: Nucleotides come as Adenine, Thymine, Cytosine and Guanine, and Guanine is the scarcest.
Run modifiers
Shape each run your way
Craft modifiers with nucleotides and materials, or find them in runs, then load up to three different ones before you head in. Every modifier has an upside and a catch, and some add a mechanic of their own, like Viral Snowball, which stacks damage for every room you clear without getting hit. Load the right ones together and a combo adds a bonus on top.
- Stock: Each run in any Game Mode uses one of every loaded modifier, which stays loaded while you have more.
- Found in runs: Cleared fights, bosses and higher-tier elites can drop modifiers straight into your stock.
- Locked mechanics: A modifier built on a mechanic waits until that mechanic has shown up in a run.
- Combos: Each pair or full trio rolls a tier once, and unloading it won't buy you a reroll.
- Mutations: Once in a while, a freshly rolled combo mutates into something much stronger.
Challenges
Fresh goals every day
Every day brings an Easy, a Normal and a Hard challenge, and every week a Normal, a Hard and an Elite one. Behind them sit hundreds of permanent milestones in chains whose targets grow with every step, covering everything from kills and bosses to gear and the Petri Lab. Finished challenges wait on the Rewards tab until you collect them, one at a time or all at once.
- Rewards: Every challenge pays nucleotides, Polymerase Shards and XP when you collect it.
- Top tiers: From Hard up, challenges add gear, and Elite and Legendary ones add skill points.
- Gear fit: Reward gear suits the virus you're playing, never above what your deepest organ allows.
- Chains: Only the next step of each milestone chain shows, and finishing it reveals a tougher target.
- Resets: New dailies arrive at local midnight and weeklies every Monday, and progress doesn't carry over.
Unlock schedule
A game that grows with you
A new save starts simple, with just Infect a Host on the main menu, and the game opens up one feature at a time as you level and your lineage grows. New in-run mechanics, from power-ups to Killer T cells, unlock for the whole save and arrive one per run with a NEW MECHANIC UNLOCKED card. Reaching a new organ for the first time opens deeper skill rows, better gear and fresh starting points.
At a glance
- Teasers: The menu shows only the next locked feature and tags each new one NEW.
- Gentle start: Early runs have smaller rooms and shorter fights that grow to full size as you level.
- New viruses: Three more viruses open as you level, and each turns up in your very next mutation offer.
- Wider pool: Higher levels bring new trait families, better trait tiers and new Game Modes.
- Adaptations: The first time your lineage reaches certain organs in Infect Game Mode, three viruses adapt for good.