Peacekeepers, how do they spawn and how do they go away?

The Peacekeepers_MegaEventDefs.xml gives them a 50% chance of spawning starting at turn 100 when there has been war for 10 turns, probably consecutive turns.  I think they stay until destroyed, but I'm not sure.  They become idle when there is no war.  In Crusade, they seem to go idle when the race they are attacking ends its wars instead of attacking other races that are still at war.

grr... I don't get why they "choose" a race to attack..

They should just attack anyone who is at war equally.

Couldn't agree more!!!

I'm playing Crusade, so they're just going to sit around until I muster up a fleet to take them on?

That's not so bad. I ended the wars because the Peacekeepers would pop out of nowhere to take out bases ans support ships behind my line. 

I could swear I have seen the Peacekeepers attack both me and an AI player.  I lead some peacekeepers into a rival faction's fleets.  They seemed to take the available target.

I've watched them mow down all of my forces while the Drengin follow them to my now defenseless planets.

I refuse to buy that DLC because there was zero interest in investing tons of hours to build an imperium, fend off the A.I. and then watch Peace Keepers annihilate all I've accomplished

Luceo Non Uro

Which DLC so I don't buy it?  (Or do.)

Megaevents.

Already got it.  Phoo.

Hmm, it's not that bad. I made peace quickly and waited for my fleets to buildup in scale and tech. 

In a way, it's kind of a blessing as I was easily ahead of the pack (1st in most relevant areas against 30+ AI races that were gifted to incredible). This forced me to consider something besides simply squashing all my opponents in an early snowball.

Can you edit that file to have them come in later, and only after more war turns?  I just changed mine.  Hope it works!  I set them to have a 20 percent weight vs 50, only appearing after turn 200 and 50 turns of war.  Hopefully that will keep those pricks from wrecking any more of my games.  I figure if they appear after turn 200 I'll have the tech to stand up to them.

Actually yes, it very much IS that bad.  In the game I just quit playing I tried to make quick peace with the Iconians when the Peacekeepers showed up, but I offered my entire list of available tech (I have a bunch of them), credits, all of my available mined resources, and some other tradeables.  They wouldn't take it.  I had no way to make peace, and the Peacekeepers were WAY stronger than I was.  It was sickening watching them plow through the assets I had worked so hard to build up.  And to rub salt in the wound they didn't touch any of the assets of my fellow combatants, as far as I could tell.  The Peacekeepers, as currently implemented, are a monumentally stupid feature.  The idea has merit.  It could be done to fit better into the context of the game.  That actually sounds like it would be fun.  But as built right now, the Peacekeeper idea is dumber than dirt.  They have sucked every ounce of fun right out of the game every time they've shown up in my games.  Stardock, you are better than this.  Fix this ridiculousness!

The last couple games I've played they have not appeared. But in the ones they have, though they can cause some serious problems, scavenging their ships has helped me immensely.