How to Build Defenses in Xterium — Composition, Levels, and What Each Defends Against

Defenses protect the planet from the enemy fleet. Building them haphazardly isn’t worth it: different weapons have different targets, and the domes work in conjunction with the weapons. Below is a guide on how to set up an effective defense. The composition, classes, and which weapons are effective against which fleets have been verified against the game code; the balance tips come from the community.

First, it’s important to understand the mechanics: defenses leave no debris and are partially restored after battle—more on this in the article Defenses: How They Work. To build defenses, you need a shipyard and combat research.

Where did this guide come from? The names of structures, weapon classes, and the “which weapon against which fleet” table are taken directly from the game code of Xterium War of Alliances (defense combat parameters). Tips on defense composition are community recommendations from the player wiki and this forum thread (authors include players Storm22073, Shataev, Kara, and others). For exact numbers, see the encyclopedia.

Two Roles in Defense: Turrets and Guns

Defense consists of two different things:

• Shield domes — small, medium, and large. They have no attack capability—they are “shield walls.” They absorb damage and provide cover for the guns. The larger the dome, the sturdier it is (the small one has a much smaller shield, while the large one has one that is orders of magnitude larger).
• Weapons—Guardian, Panzer, Hammer, Achilles, and Prime systems. These are the ones that fire on the enemy fleet.

The point is this: the domes absorb the impact while the guns are firing. Therefore, a proper defense consists of both the domes and the guns together, not just one or the other.

Weapon Classes — Against Different Fleets

Weapons are divided into three classes, plus a "Prime" class. Each class is most effective against ships of "its own" class:

In other words, light guns are excellent for taking out small ships, but are almost useless against a heavy fleet—and vice versa. Therefore, to counter a diverse fleet, you need a mixed defense comprising all classes.

What are the differences between the Strazh, Panzer, Molot, and Achilles?

Within each class, there are four "families" of vehicles—each with a different type of weapon:

• The Guardian is a laser weapon;
• Panzer — an ion cannon;
• The Hammer is a plasma weapon;
• Achilles is a class-based combination weapon.

The type of weapon matters because ships and domes have different shields and armor—some weapons penetrate them better than others. At the start, there’s no need to overcomplicate things: just pick up a few different weapons of your class to cover a variety of targets.

What kind of defense should a beginner build?

1. First, the domes. The small dome is the cheapest form of protection; it absorbs damage and shields the guns. Place a few of them.
2. Next, light cannons (DL). Early on, you'll often be attacked by a light fleet—and light cannons are perfect for dealing with it.
3. Weapons—in large numbers, not just one at a time. A single turret doesn't make a difference; defense relies on sheer numbers.
4. Medium and heavy ships—later on, once you've upgraded your combat research (Shields, Armor, and Attack to the required levels) and when you face opponents with larger fleets.
5. Save Prime Defense for last: it's the most powerful, but it also has the highest requirements.

It’s important to remember from Defense Mechanics: Defense units leave no debris behind and are restored to 50–70% of their health after battle, so in the long run, they’re cheaper than a fleet. However, a “bare” defense without a fleet won’t stop a large, experienced attacker—defense complements protection, it doesn’t replace it.

Common Mistakes

• Just the domes, without the guns. The domes don't fire—without the guns, they just go down in a spectacular fashion.
• Only guns without turrets. Guns get knocked out quickly if there's no one to shield them.
• One class of guns. Light guns won't stop a heavy fleet. You need a mix of weapons tailored to the target.
• One turret at a time. Defense relies on numbers; individual turrets are useless.
• Focus solely on defense. A large fleet will break through your defenses—it’s better to “save” a strong fleet (see How Not to Lose Your Fleet).

Frequently Asked Questions

Where should I start when building defenses in Xterium? Use shield domes and light units. The domes absorb the damage, while the light units (Guardian/Panzer/Hammer/Achilles DL) take out the small fleet that new players are most often attacked by. Place your turrets in groups, not individually.

Which weapon is best against which fleet? Light guns (DL) are used against light fleets, medium guns (DM) against medium fleets, and heavy guns (DH) against heavy fleets. Each class is strong against “its own” and weak against others, so a mixed defense is needed against different types of fleets.

What is the difference between the Guardian, the Panzer, the Hammer, and the Achilles? These are turrets with different weapon types: Guardian—laser, Panzer—ion, Hammer—plasma, and Achilles—a combined-class turret. Each type penetrates targets’ shields and armor differently.

Why do we need domes if they don't shoot? Domes act as shields: they absorb damage and protect the guns. Without domes, the guns get knocked out faster. That’s why defense involves both domes and guns working together.

Will a defense protect against any attack? No. Defense complements protection and is effective against small raids, but an experienced player’s large fleet will break through it. It’s better to hide (“save”) your own strong fleet rather than rely solely on defense.

What to Read Next

You'll find these guides useful: Building Order, Which Research to Upgrade, and how not to lose your fleet. Useful mechanics include defense: how it works and the list of structures in the [Defense] section](/knowledge/encyclopedia/defense). Slang terms can be found in the dictionary.