Tech tree
Three tiers, three production lines, and the Radar Station that gates the top.
Steel Tide has three tiers and no research. Tech is buildings:
- Tier 1 is whatever a basic factory produces.
- Tier 2 unlocks when the factory is upgraded in place: War Factory → Advanced War Factory, and likewise for the Airbase and Naval Yard.
- Tier 3 needs the upgraded factory and a Radar Station standing anywhere in your base. Lose the radar and Tier-3 units leave the build menu until you rebuild it.
Engineers come from the Headquarters and construct everything else; buildings have no tech requirements of their own.
Upgrades
Every upgradeable building upgrades once, in place, keeping its position and its production queue. The upgrade costs metal and time on top of the original building and, once finished, draws more power.
| Weapon | Cost | Build time | Hit points | Power | Upgrade |
|---|---|---|---|---|---|
 | 120 | 10 s | 600 | −4 | 240 metal · 16 s |
 | 140 | 12 s | 500 | +20 | 260 metal · 18 s |
 | 320 | 20 s | 1500 | −8 | 420 metal · 25 s |
 | 380 | 24 s | 1400 | −8 | 450 metal · 26 s |
 | 350 | 22 s | 1500 | −8 | 450 metal · 26 s |
 | 130 | 10 s | 400 | −2 | 260 metal · 16 s |
 | 320 | 18 s | 700 | −3 | 420 metal · 22 s |
 | 240 | 14 s | 500 | −3 | 320 metal · 20 s |
Timing
- Upgrade the factory you actually use first; a second basic factory is rarely better than one advanced one.
- The Radar Station is cheap for what it unlocks, but it is also a target. Build it when you can defend it.
- Turret upgrades are worth it on the side the enemy attacks and wasted everywhere else.