Defense
While ships are indispensable for offensive actions, there are defensive structures for defensive players to allow them to protect their planets from other players. Those are built the same way as ships and from then on are always ready to fight against attacking ships. Depending on how many defenses one builds, one can defend more or less resources from other players, as a big defense makes attacks unprofitable for other players.
Though there are also those players who systematically attack heavily-defended planets (so called turtles).
Balanced buildup
When building a fleet there are some major points you have to pay attention to. The same goes for defenses. The amount of defensive structures should always be matched with the needs of the planet / moon the defense is built on. If your goal is to just save those res you produce over night it would be overkill to build a huge turtle worth some hundred-thousand points.
Though if you want to defend your whole fleet (at least for a while) you of course need a much bigger defense. The right mixture of the different units is very important too. Analog to small ships, small defensive-units later take the role of "cannon fodder", while you build the big guns for the big bang.
But no matter how strong your defense is and how well thought-out its design, the best defense is the one that's never used. When you're unprofitable for even the strongest players in your universe you're almost 100% sure to not be attacked.
Exceptions are:
- above mentioned "turtle-hunters". They'll smash you to pieces just for fun.
- You play in a special universe where a certain % of the defense-cost goes to a debris-field when its destroyed (def-to-DF-unis). In such unis a big defense is like a free BBQ for all players with a strong fleet, as defense can't run away from an attack. To find out more information about your universe's features see Universes and Player
Chance of reconstruction
As said, defensive units can't fly or magically disappear, so they can't be saved from attacks. But if they are destroyed during an attack its not the end. In ogame every type of defense has a chance of 70% to be repaired after it was destroyed during an attack. If you use the premium-feature "engineer" the chance is 85% (see Premium features).
This feature doesn't allow your enemies to wipe out your defense in just 1 run. They have to fly numerous attacks against your planet before everything is gone. Another way to destroy defense is via using Interplanetary Missiles.
The different defensive units
Even though all defenses have the same purpose, to protect your planet from enemy attacks, some units are more specialized then others. Its basically the same as with fleets. All units play their own important part, but only in combination with the others are they the most effective.
In the earlier gamestages even 1 small shield dome alone can fend off a whole enemy fleet, in case it consists only of cargoes. That is because those ships lack the attack strength to penetrate the shield itself and thus can't destroy the dome.
You can only build 1 small shield dome per planet.{{Detail-Defense|Anti-Ballistic Missile|Anti-Ballistic Missiles are a special type of defensive unit. They're not designed to fight enemy ships, but instead to shoot down incoming Interplanetary Missiles at a rate of 1 to 1.