Combat
When your fleet arrives at another player's system with non-probe ships, a battle plays out between your stack and what's parked there.
How to win
Bring more ships, and bring the right kind. Mass advantage compounds. A roughly even fight grinds both sides down, and even a 2-to-1 edge still leaves the smaller side standing while you pay real losses. Bring a bit more than 2-to-1 or steeper and your fleet presses a second wave that tends to wipe the smaller side cleanly.
Ship choice matters as much as numbers. Marauders hit hard but bruise easily, so they're the right pick for attacks. Sentinels hit softly but absorb a lot of damage, so they're best left at home as defenders. A Sentinel-led attack on a defended system is wasted iridium.
Outcomes are never fully deterministic and even decisive fights have some random spread.
Drones
Probes behave differently depending on the side.
Attacking: probes don't fight. They tag along, sit out the main battle, and always fly home. Even if your whole combat escort is wiped.
Defending: probes do fight. They're fragile but they soak hits.
Credit deficit
If your treasury is empty, your ships fight at reduced effectiveness, so they hit less hard AND less often. Keep income from Trade Hubs ahead of fleet upkeep before you commit to a fight.
When a much larger empire attacks a much smaller one, the attacker also fights at reduced strength, see Morale.
Rewards
Surviving attacker ships carry palladium and iridium home from the defender's stockpile, capped by your fleet's cargo capacity. Marauders have the largest hold, so a raiding fleet wants them not just for the offense but for the loot.
After the battle
Surviving defenders stay parked. Surviving attackers immediately turn around and fly home, carrying any plundered loot.
