Tech tree
Which buildings, units and research you unlock and in which order. The same on every server.
Buildings
A building becomes available once you own at least one building from every level below it. So any one building per level is enough, not all of them.
1× One-time building: can only be built once and is never lost in attacks.
Military buildings & defense
You build these once and then upgrade them level by level. Every upgrade level unlocks a new unit.
| Level 1 | Level 2 | Level 3 | Level 4 | |
|---|---|---|---|---|
| Barracks | Soldier | Panzer Grenadier | Elite Soldier | Combat Diver |
| Weapons Factory | Lynx | Mine Clearer | Challenger 2 | Mobile AA |
| Shipyard | Cruiser | Destroyer | Typhoon Submarine | Aircraft Carrier |
| Aircraft Hangar | Apache Longbow | Comanche | Eurofighter | B-2 Bomber |
| Land Defense | MG Position | Mine | Artillery Position | |
| Water Defense | Underwater Mine | Coastal Gun Turret | Coastal Artillery | |
| Air Defense | AA Position | Patriot System |
Research
All research needs a research center (level 3). An arrow means: the previous research must be finished.
Technology
On each tier you pick one of two research projects, the other one is locked afterwards. A finished research project on one tier unlocks the next tier.
Unit upgrades
Reinforced armor can be researched at any time. For the others you choose one branch, the other one is locked afterwards.
Espionage
Housing quality
Four lines with two levels each, independent of each other.
Weather
Also needs a weather station (level 6).
Resource research
No requirements, can be repeated as often as you like. Every level costs more.