I attacked another empire's capital and all its sector capitals at the same time. The enemy's capital became a second capital for me and the other empire wasn't destroyed even though it didn't have a capital any more.

When this happens it becomes impossible to message the attacked player or check their fleet size/imperial might, since their empire no longer has a capital. They can still establish new sector capitals, which will project influence as normal, but they can't change doctrines and no name will show up for their empire on the zoomed-out map. The captured capital will retain whatever its original doctrine was, even if the capturing player has a different doctrine.

also it looks like the other empire can't abdicate since they don't have a capital.

The second capital doesn't project influence, can't be re-designated, and can't be issued orders if it's not inside the influence range of another capital. The original owner will still be centered on this planet when they log in.

The Empire tab can appears on all surviving planets under the no-capital bug; but abdication is impossible if all planets are lost

6cef 30 Sep 2016:

Tried to recreate this bug. Did not happen in following scenario:
Small galaxy with 10 worlds. 2 player empires w/1 world each. Mesophon & 1 NPE.

Player 1 empire attacked and conquered player 2 empire capital. World was captured successfully and designated autonomous. This seems to be the correct behavior.

Does not trigger (Empire 1 always conquers empire 2):

  • Empire 1: 1 empire capital. Empire 2: 1 empire capital.
  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, 1 sector capital.

Scenarios to test:

  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, 1 other.
  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, 1 other. Capture simultaneous.
  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, 1 other. Capture between Empire 2 logins.
  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, 1 sector capital, 1 other.
  • Empire 1: 1 empire capital. Empire 2: 1 empire capital, n sector capitals, n other.
    • Empire 1: multiple world permutations. Empire 2: multiple world permutations

Player IMPERIUM ASCENDANT reports that the captured second capital TERRA now projects an influence range.

lazygun 8 Oct 2016:

Player University (not original owner of TERRA) counterattacked IMPERIUM ASCENDANT. TERRA is now a standard independent world. (renamed as "unbugged")

Confirming that sector capitals can sometimes be captured intact (retaining their designation) without accompanying defections. This happened in my recent war against Union of Free Worlds; the affected capital has been renamed "retained designation"

george moromisato 2 Mar 2017:

This is fixed in the latest build.

The problem was that the various conquest paths usually relied on designating the conquered world in various ways. For example, when conquering a capital we need to re-designate it to an autonomous world.

But due to various bugs, the designation was failing and causing the conquest to abort in the middle, leaving the empire broken (e.g., no capital for an empire).

Usually, the reason for designation failure was lack of tech level. For example, when conquering an enemy capital we would try to pick a sector capital to replace the original capital. But due to a bug, we sometimes picked a sector capital that was too low in level. When we tried to designate it as a capital, the designation would fail and we would abort the conquest code.

I've fixed this in a few places. The most important change is that all the conquest code checks to make sure it can designate something before proceeding. In particular, the when choosing a new capital, we make sure we can designate it before proceeding. [This goes through a common code-path, unlike before, so it should be resilient in case of changes.]

See also: https://forums.kronosaur.com/viewtopic.php?f=48&t=8007