01 Virus resistance
// RESISTANCE IS SURVIVAL
The virus is the spine of the season, and resistance is how you survive it. Every battle inside the contaminated world risks adding infection stacks to your troops and base — and resistance is what slows that accumulation.
Infection is tracked in stacks from 0 to 100. Let it climb unchecked and the debuffs worsen at every threshold, peaking at 100 stacks — the worst outcome in the season's economy. The higher your resistance, the slower stacks build and the safer every fight becomes. This is why the Virus Research Institute is a first-week priority, not an afterthought.
// Rally rule worth knowing
In a rally, the leader's resistance applies to the whole group if it's the highest of the five. If an ally has better resistance than the leader, theirs holds and can carry the rally. Always check required resistance before hitting zombies or corruptors.
02 Infection & the contaminated zone
// THE ENVIRONMENT YOU FIGHT INSIDE
The season's map is a contaminated world. On non-war days, battles are restricted to the contaminated land, and the virus moves between players through combat. Knowing how it transmits keeps you from spreading it to yourself by accident — or lets you weaponize it on purpose.
How it transmits
When an infected base sends troops out, those teams carry roughly 25% of the base's virus stacks with them. Attacking a base behaves by its defense state: a base with no defense transmits infection to you; a base with defense but no troops transmits nothing; a base with defense and troops passes on the virus stacks its troops carry. Curing is done through healing — request cures in alliance chat quickly to avoid the heavier debuffs that stack up near 100.
Reading the stack count
Infection runs from 0 to 100, and the number matters at specific thresholds. Below about 20 stacks you're clean — no penalty. From 20 upward the combat debuffs begin. By 40+ your casualties climb sharply, by 60+ troops carry more infection on the march, by 80+ they can infect enemies even in defeat, and 100 is the maxed, worst-debuff state — the outcome you never want. You can shed stacks by attacking a healthy player, transferring the infection off yourself and onto them. One weather caveat: Acid Rain prevents stacks from reducing, so if you're stuck climbing during Acid Rain, a cross-server teleport is the reset. And offensively, the Engineer Virus Shell skill applies 30 stacks to a target — a deliberate way to push an enemy toward their own 100-stack ceiling.
03 RA virus goals — infect, cure, spread
// ONE OF THE EASIEST REWARD LOOPS IN THE SEASON
This is the system most players walk past, and it pays out all season. The game rewards you for infecting, curing, and spreading the virus — the more you do it, the more chests you open. There's no real cap on the rewards; the only limit is your stamina.
The goals unlock in stages — infect your troops, cure allies, and spread the virus — each paying out speedups and diamonds. Every heal you perform also returns a Gene Fragment, which feeds Genetic Recombination below.
The trick to "spread the virus"
Spreading is the goal players struggle with, for a frustrating reason: their own alliance keeps auto-healing them, which resets the progress. The fix is built into the game — the Pathology tab has a "Don't allow allies to heal me" checkbox. Switch it on while you're working the Spread goal so your stacks can climb, then switch it off when you're done. You can also spread deliberately by defeating enemy commanders, transferring virus to weaken them while you bank the reward.
// Feed the goals by hunting bosses
The boss hunt and the goals reinforce each other. Doom Walker first-blood kills are a daily Mutant Crystal source, and the Virus Control profession skill lets you defeat a Wanderer of the Damned to receive a summon item for attacking a specific target. Hunt them while you're working your virus goals — the same activity feeds both.
04 Weather system
// THE ENVIRONMENT THAT CHANGES BY THE HOUR
Season 1 has live weather, and it's not cosmetic — it shifts virus accumulation, march speed, and profession EXP. It goes live around Day 3, each server runs its own weather independently, and it changes on a cycle (roughly every 30 minutes to several hours). The forecast (read it via Monica) shows three possible conditions with probabilities, but the final result is random — so plan, don't assume.
| Weather | Effect | Play it by… |
|---|---|---|
| Acid Rain | Auto virus accumulation, reduced defense | Avoid big battles — or use it to spread virus in PvP |
| Foggy | +1 virus stack per battle (monsters start with more) | Heal more; fight carefully |
| Windy | March speed −30% | Recheck rally and reinforcement timing |
| Light Rain | Troops carry no virus stacks | Safest window for Elites and tough PvE |
| Sunny | +30% profession EXP from killing monsters | Best time to rush levels |
| Rainbow | Passive profession EXP gain | Ideal for farming resources |
| Cloudy | Neutral — no effect | Business as usual |
Always check the weather before any cross-server move. Windy can quietly wreck a rally's timing, and Acid Rain can turn a routine fight into an infection problem.
05 Seasonal buildings
// WHERE YOUR SEASON POWER COMES FROM
Three seasonal structures anchor your growth. Prioritizing them in order is most of what "playing the season right" means.
Virus Research Institute (VRI)
Your resistance engine. The VRI raises virus resistance, which protects your troops and base all season — the single most important seasonal building to push early. Level it to 30. At VRI 30 your siege losses drop to near zero; at low resistance you can take something like a 99% damage penalty in season combat, which turns a winnable fight into a wipe. (Note: it's the Virus Research Institute, not a "research initiative" — the distinction matters because resistance is the whole point.)
Protein Farms
Sustain and supply. Farms keep your economy fed so you can keep building and training without stalling.
Military Bases
Defend, expand, dominate. Military Bases unlock around Week 3 and underpin the territorial side of the war.
06 Engineer vs Warlord
// THE PROFESSION CHOICE THAT SHAPES YOUR START
Start as Engineer. For almost everyone, this is not a debate.
The Engineer profession accelerates building, research, and economy — the foundation everything else in the season stands on. The Warlord (attack) profession is powerful, but it's nearly wasted before you have the HQ level and T10 troops to make it count. Open as Engineer, build the base that makes you dangerous, then switch — switching later is cheap, but starting wrong burns weeks. Upgrade every profession skill that grants EXP along the way.
// When to actually switch
Stay Engineer for 90%+ of the season — this is the right call for almost every account. The only time to switch to War Leader (Warlord) is around Week 5–6, and only once three things are all true at the same time: you're HQ30+, you're running T10 troops, and your base development is essentially complete. Before that, the attack profession is wasted; after that, switching is cheap. If any one of the three isn't true yet, stay Engineer.
07 Genetic Recombination
// TURNING GENE FRAGMENTS INTO POWER
Every heal you perform in the virus-goals loop returns a Gene Fragment. Genetic Recombination is where those fragments are spent — combined into Mutant Crystals, the primary Season 1 building resource. It's a slow, compounding system: the players who work their cure goals consistently feed it without thinking about it, and come out ahead by season's end.
Each recombination needs one of each fragment, types I through VI. The split is what makes it a loop: I, II and III drop from attacking zombies and Doom Elites, while IV, V and VI come from curing infected alliance members — so the fastest path runs zombie kills and ally cures side by side. The ones you'll usually be short on are IV–VI, since they depend on having allies to cure.
// Trading fragments in chat
You can trade spares with the alliance, but keep it disciplined: post your excess in chat, run one active trade at a time, and replace it daily so the board stays current. A tidy trade lane is how the whole alliance finishes recombinations faster — not just you.
08 Tech tree
// RESEARCH IN THE RIGHT ORDER
Tech is power you research instead of build, and order matters. Early on, prioritize the development and economy branches — they speed up everything else. Then move into the squad, unit, and hero branches as your combat matters more.
One line is non-negotiable: absolutely upgrade City Durability tech. Once city wars begin, durability is what keeps a city standing long enough for reinforcements to arrive — without it, even a strong city can fall in seconds. Alongside that, upgrade everything that grants profession EXP to keep your Engineer benefits compounding.