I'd like to know what the deal is, how good it is, and when it SHOULD be used.

So how long has this concept been in this game, and nobody talks about it?

invasion defense works just like regular defense EXCEPT, it only is factored when when the invasion is tried ( not during the attacking of the planet. ) So in effect, you could have an invasion defense of lets say 40k, with a planetary attack / defense of 0. theres not going to be alot of people taking that out, especially - and correct me if im wrong - because zolazin sabs CANNOT target invasion defense structures. thus your planet would be real easy to beat down, but really hard to actually take.

Thank you for the information. I'm sure this will help some newer players, should they see this.

Depends on the structure. The soldier outpost, and I think there is anotherone, can be sabbed.

Lazuli Pylon?

hmm true, solder and council base can both be constructed, so those possibly could be sabbed. Forgot about that.

You didn't do a search did you. There are MANY threads that discuss invasion defense.

I did do one search, but I didn't find anything. To be fair, They didn't have the phrase "Invasion Defense" as, or part of, the title

I searched and you are right, I could of swore there was a rash of invasion defense posts not long ago, but i cant seem to find them.

They must just be difficult to find, I myself posted a thread about this very subject in order to learn all the specifics, though that was quite some time ago.

here are a couple:

viewtopic.php?f=3&t=22674&start=0&hilit=invasion+defense

viewtopic.php?f=4&t=22033&start=0&hilit=invasion+defense

So, the best way to increase my chances of invading would be just to get my attack up?

Yes. That, and finding a legion with a lot of Sabs

And a whole bunch of artis.

That's what I'm asking. I've disabled planets fairly quickly but I've still failed with a something ridiculous like a 75% or 80% chance of invading. I'm trying to figure out what I have to do on my ship to stop that from happening.

Nothing, it happens to everyone, it's just luck.

After invading a planet each day working on the new medal on like the 5th or 6th day I failed 2 or 3 days in a row at 90% success. I think it was 3 days in a row and it was the same planet.

Planet X invade 90% fail
Next day Planet X invade 90% fail
Day later Planet X invade 90% fail... I think I got it the next day after that. And that is 90% success invasion.

Yeah. I've run into a planet or two like that. That's what kills me. I could understand if that planet had a Lazuli Pylon or some other invasion defense buff but I've run into planets with common structures on it and no defense whatsoever and still hit that wall. I truly hope it ISN'T just luck because if it wasn't for bad luck, I wouldn't have any.

It is down to luck, if you have a 90% chance and fail then it's that 10% that's stopping you.