I.... I just ended a 50 year long war in a white peace. Defense stations held off my otherwise certain doom.
Context:
So, I start a new hard Ironman game with agressive AI, because, despite doing well with insane AI before patch 1.1, after the patch with high aggressiveness on, insane AI was handing my ass to me within the first couple decades. I'd figured that hard would be sufficient with the AI being aggressive enough to war before I get things together.
The race I chose was a race of fanatic materialist long lived space mollusks lead by a council of scientists named the Tythean Council which, of course, spawns next to a race of evangelizing zealots that want my people's heads on pikes. Before a decade is up, I get rivalled. From my experience with insane agressive, I knew this meant that shit was gonna get real in the next 5 years, period. The guy has slightly better fleet strength, but a preemptive war with a decently teched fleet for early-game makes the war winnable. So I took 3 planets right off the bat and wiped out the other empire, and things are going relatively well despite the fact that I had to spend all my influence for a couple decades afterward to get the new planets in line. Of course, this ruins my research, but it's no big deal since the guys to my north love me.
And then I found out who was to my south. The krogan(from a mod). They rival me ASAP, and I know shit's gonna hit the fan. Their fleet is overhwhelming and the only other empire that's rivaled them is on another arm of the galaxy. I'm only just getting to the point where I can make destroyers. So, I start building defense stations en masse. And, within 5 years, they go to war.
Predictably they attack my empire's capital world, which is awash in basic defense stations and has my measly fleet 1k fleet guarding it with an admiral that can't retreat. They bring in their 3k fleet. After all's said and done their 3k fleet is reduced to 600, but everything I have in my capital system is wiped out.
Fortunately, my planet is heavily fortified with a robot army. They decide, after a failed land invasion, to pull out and get their fleet back together, and the warscore is -35%. They're pestering me to end the war by giving them my capital world. I have to spend 100 influence four times in order to prevent the war from ending, ended up having to do some hit and run with small fleets to get the war score to the point that they stop asking.
By this point I notice that about 1/3 of their ships use missiles, so I build some point-defense ships. All of their ships also have heavy shielding, which make my plasma cannons less useful, so I research disruptor tech for the next wave.
They give me enough time to get a real defense up:
(this is the second time they throw their fleet at it)
I learned from previous games that the first defense station you put up becomes a point that whatever fleet jumps in gets pulled to, regardless of module. So, the first defense station I make is a throwaway defense platform that uses a shield dampener. I then surround that defense platform with full defense stations that have the minefield modules; and all of those mine fields overlap with the sacrificial platform. I have, by this point, rebuilt a 1k fleet by dumping all my minerals into 4 different spaceports before the first strike.
The first time they throw their fleet shiny new 4k fleet against it, it's an absolute slaughter they're forced to retreat from, but I'm left with only a 500 fleet that's injured and they have the same amount remaining. I strike back a bit, destroy a couple of space ports, get into a couple of skirmishes(my new admiral can actually retreat, which helps), and then run away from their rebuilt fleet that's twice mine's size and actually has cruisers, while I didn't(90% corrvettes because they wrecked my good spaceports).
Then, second attack against my defense shield comes:
This time they have more cruisers and destroyers than corvettes and the mines are significantly less effective. They manage to take down several defense stations, but their fleet is decimated. Warscore is up to +1% and I see that they're willing to accept a white peace(the war is so long that they have a huge buff to willingness to end it).
I go to strike back again, with about 800 left. I rebuild my fleet in the meantime. I start sieging their planets and get ready to invade... When they attack with a fleet full of cruisers.
I decide to let things play out until I see my fleet go down to 345. I send a peace proposal that's accepted just in time to save my admiral's ass.
Thus ends the 50 year long Krogan-Tythean war. Both sides bled heavily for absolutely no gain.