I took you at your word in your first post....

But I remembered latter, the fates ARE related.

It's less a chained fate and more a cycle of fates.

If the defence goes badly, you end up in one point, if the defence passes another group invades.

Mess, Misfortune, Mishap and Misadventure.

Are you trying to get the minion? The junkmonger shows up with it after two defences in a row I think?
Or the achivement for defending it through the entire series?