System guide · Defense
Zyrex Defense in Wall World Strategy
Zyrexes are the creatures living in the shadows of the Wall, and they attack your colony again and again. Each wave tests your fortifications, how well the colony is organised and how fast you respond. On top of the waves, accidents, disasters and environmental hazards hit the colony and set off chains of smaller problems. This sheet covers the defensive tools Alawar has confirmed and the order to prepare them in.
Repeated waves How zyrexes attack
4 Listed defense and combat changes
Cheaper Concrete defense wall after the Demo Update
Still attack Zyrexes in Sandbox Mode
Before the next wave Close the gaps in your wall line, check that the buildings you cannot lose are covered, and keep the colony able to absorb an accident at the same time as an attack. Emergencies will not wipe the colony out on their own, but they stack on top of a wave.
Sheet 01
Raise walls on the Wall
- Fortifications are buildable — Asked on the Steam forum whether the game has walls, the developers answered yes: you can raise walls around the colony for better protection against incoming zyrexes.
- Concrete is the cheap option now — The Demo Update made the concrete defense wall cheaper to build, so ringing a growing colony costs less of your early resources than it did in the first demo build.
- Decide what to protect — The store page asks you to secure vulnerable areas and judge how much you can afford to spend on protection. Every resource put into walls is a resource not spent on production or housing.
- Roads are also attack paths — Enemies move through your city. The Demo Update improved how both robo-spiders and enemies navigate it, so the way you lay out roads and stairs shapes where zyrexes arrive.
Linked changes
- Balance — Concrete defense wall made cheaper to build — Demo (June 2026)
- Improved — City navigation for robo-spiders and enemies — Demo (June 2026)
Sheet 02
Shield key buildings and watch the panels
- The small energy dome — A small energy dome structure can be switched off and on. The Demo Update fixed bugs that appeared when players disabled it, so toggling it is now safe.
- Use the wave panel — Playtest v0.3.0 refined the wave panel together with the resource, weather, task and research panels. Check it between attacks to see what is coming before you commit resources.
- Follow off-screen indicators — The same playtest update added indicators that point to important events happening outside your view, so an attack on the far edge of the colony does not go unnoticed.
- Enemies pick targets — Enemy movement, target selection and attack behaviour were improved in playtest v0.3.0, along with new combat and explosion effects that make hits easier to read.
Linked changes
- Fixed — Bugs when switching off the small energy dome — Demo (June 2026)
- Improved — Enemy movement, target selection and attack behaviour — Playtest v0.3.0
- Added — New combat visual effects — Playtest v0.3.0
- Improved — Explosion visual effects — Playtest v0.3.0
Sheet 03
Emergencies between waves
- Accidents and disasters — Emergency events such as accidents, disasters and environmental hazards disrupt how the colony runs and trigger cascading problems instead of destroying it instantly.
- Rockslides — Demo players reported a rockslide event: the camera pans over to it when it happens. Treat it as a cue to check damaged buildings and the roads they depend on.
- Repair what breaks — Damage needs repairing, and the repair system was reworked between the playtest and the demo. Keep resources in reserve so a wave and an accident do not both drain them.
- Morale holds the line — A well-supported population recovers faster from attacks, according to the store page. Food and housing problems make every attack hurt longer.
Linked changes
- Added — Off-screen indicators that point to important events — Playtest v0.3.0
- Fixed — Event pop-ups no longer interrupt controls in build mode — Demo (June 2026)
Sheet 04
Defense trade-offs
Protection competes with the rest of the colony for the same resources. These are the four calls you make every time the colony grows.
Sheet 05
Defense elements at a glance
Each defensive element named in official posts and developer replies, with the build where it first appeared in a list.
| Element | What it does | Described in |
|---|---|---|
| Zyrex waves | Creatures that attack the colony repeatedly, testing defense and organisation. | Playtest v0.3.0 |
| Defense walls | Buildable fortifications raised around the colony. | Developer reply on Steam |
| Concrete defense wall | Wall type made cheaper to build in the Demo Update. | Demo (June 2026) |
| Small energy dome | Structure that can be switched off; disable bugs fixed in the demo. | Demo (June 2026) |
| Wave panel | Interface panel tracking incoming waves, refined in the playtest. | Playtest v0.3.0 |
| Off-screen indicators | Markers pointing to important events outside the camera view. | Playtest v0.3.0 |
| Emergency events | Accidents, disasters and hazards that disrupt operations; rockslides reported in the demo. | Steam store page |
Sheet 06
Every defense and combat change so far
Four listed changes touch defense and combat directly, from playtest v0.3.0 to the Demo Update.
Playtest v0.3.0
- Added — New combat visual effects
- Improved — Enemy movement, target selection and attack behaviour
- Improved — Explosion visual effects
Demo (June 2026)
- Balance — Concrete defense wall made cheaper to build
Sheet 07