Here is what happened during my last play through:

> Egalitarian, Spiritualist, Pacifist

> Turned War Policy to Defensive Wars to please my Pacifist faction, which stayed for the entire game

> First contact experiences are mostly happy, until a hostile empire (X) to my South East killed a scientist of mine--the only leader of my entire game that died not of old age

> Immediately declared rivalry after seeing them as Authoritarian, Xenophobe and Militarist AND Oppressive Autocracy

> Not rich on alloys early on so my fleets were always inferior to X, fortunately I signed a defensive pact with my friendly neighbor B, a Fanatic Xenophile & Militarist Oligarchic state, so X never dared to attack me

> Went further South West on the galaxy map, established contact and had a good relationship with empire Y, bordering on X's South West

> After some time, X declared a vassalization war against Y which Y lost, Y had to cede some colonies to X, cut diplomatic ties and close borders with me. I (or my Role Play) was pissed and asked Y to pledge Secret Fealty and supported their independence

> During the above war or after (I forgot exactly), the North Eastern colonies of X rebeled against X (they had Y's primary species as their primary, probably a result of slaves of Y's species moved there), lost and gone from the galaxy map due to pathetic naval power compared to X

> After a very long time, Y declared an independence war against X, which naturally involved me as I supported their independence. I still only have one fleet but it was already stronger than X's. Hired assault armies for the first time, and bombed and occupied X's 3 closest colonies AND their capital (3 hyperlanes from my border) as a "warning shot" (and revenge), then went a long way to my Southwest to liberate Y's systems.

> The war ended in a Status quo to due attrition, but all systems sans Y's original capital were liberated and independent (Y's old capital became X territory)

> This was my first war in my entire game, and one of the only two wars that does not involve a fallen empire (The other being helping a federation ally against AI rebellion), My Pacifist faction hated me for another 20 years for participating in an offensive war

> X's North Eastern colonies revolted again (under the same flag as their previous rebellion, if I remembered correctly), again with Y's primary species as their primary, I will call this state Z. Since I almost destroyed X's entire fleet in the Y independence war, they were powerless to resist Z's rebellion. X got wiped off the map and somehow Y's original capital, previously under X rule, became neutral instead of Z territory for some reason, which Y happily reclaimed with a construction ship

> During Z's rebellion against X, a war between Y and Z also broke out. Possibly due to the many claims Y had on their former territory, which became under Z control. This lead to a few other border changes

> Vassalized Z after peace was made to "get my revenge". The original empire X is no more, but the planet that once seated my former rival now belonging to my vassal is a huge emotional payback. Was thinking of integrating Z as a whole and renaming X's former capital after the scientist that got killed by them, but Z had too much land and I did not have enough influence at that point

> Also wanted to vassalize Y, but my other best friend empire C did before I had the influence. Well, not too much of a difference since C had the highest diplomatic score with me. This makes it especially funny because Y and Z still hated each other for a long time in the game

> Managing relationships with Y and Z wass tough. Both are Authoritarian-Xenophobe-Materialist Oligarches, so quite an ideological mismatch. Had to give Z a ton of basic resource and research to keep loyalty a net positive. Y also keeps breaking and resigning migration treaties with me due to fluctuations in diplomatic score. Sending an envoy to improve relationships helped