Actually, they do that to prevent human players from sneaking in a transport and taking their worlds without an effort. A troop transport (unless armed) cannot "land" troops while there's a ship in orbit...and even if armed has to destroy all ships in orbit first. That is why the AI puts an unarmed ship in place, since most transports do not have weapons.

Play the game. If you find Normal too easy, there's several other difficulty settings higher.

BTW... there were so many complaints that Normal was stomping on all the new players that Normal was tweaked down a notch for the 1.1 patch.

The reason they started cranking out more is because you started taking them out. It's figuring you're going to try and sneak a transport in there, so the AI is making it tougher to do so.

It just really sucks when the AI gets a transport through to one of my undefended planets.

i live in southern california, so i don't know if this will be the case where you are. generally there are 3 spiciness levels of salsa: mild, medium, and hot. in some of the more authentic restaurants, there are 5 or more. mild, medium, hot, very hot, and masochistic. notice how 'medium' is not in the middle?

besides, it sounds like 'challenging' is an apt way to describe what you're looking for, and it just so happens to be the next difficulty level. i just started playing on tough myself.

here's a question about the game you were playing. was your military significantly stronger than theirs? yes? well, that means they're probably going to focus on defensive tactics, like keeping you from waltzing right in.

that said, i do agree. it's a strange thing to do. i haven't noticed it before, but i haven't been playing on normal for some time now (especially since they made it easier).

one more thing though: i've learned a few things from watching the AI. i also hate it when they invade an undefended planet. and this seems like a perfectly logical tactic for me to use in the right situations. earlier in the game or when a significant number of planets become yours at once (cultural revolutions and surrenders), or if your economic is strapped and you can't afford a real defense, it might be nice to have something cheap as a stop-gap measure. as it is, one of my preferred tactics when i can swing it is to have lightly armed transports double as planetary defense. if i've got military bases in the area, these ships can actually become pretty scary.

I encountered that unarmed ship thing many times. Even when the AI has a fleet flying around with attack value 3 per ship it still build unarmed ships for defense. That makes no sense, because putting in some weapons is not so much more expensive.
I saw that in the first and second campaign mission on normal and tough several times. Also now in a metaverse game on a small map on tough in a war against the Yor. I see the usefulness of an unarmed "invasion-preventer", but the AI uses the feature often in a stupid way.

What I don't like is, that I need to have that improvement to make the defending ships in orbit fighting as a fleet. Why that? I have my logistic ability for that. Period. I also don't like that I can't help a starbase in its defense with other ships.

Have you ever just built a ship without anything on it? It's like 2 bc

Tiny hull is 35. Cargo 55.

Particle beam costs 25, Sensors cost 2.

Hm... Interesting. Well, I set the difficulty to Challenging, and now, instead of building a single, unarmed defender, the computer will place two or three unarmed defenders in orbit around their colonies, even when they have access to such esoteric technologies as Laser V.

There's a defensive block measure, and then there's insanity. Wouldn't it have been better to stick a laser on one of those defenders rather than create 3 blank blocking ships?

I have heard a lot of players talking about using the same strategy themselves with unarmed ships. Also, to criticizes a game's AI while playing only on levels where the AI is crippled is ridiculous. It's crippled at those levels on purpose to help gimps, little kids and newbies be able to enjoy the game even though they suck at it. If you havent even beaten the AI on Tough (which is far from the most difficult level) you shouldn't be complaining about the AI...since you haven't played it yet, lol. That is like saying "Hey, that guy with his hands tied behind his back doesn't pack a very good punch".

I'm not sure if a planet defender with zero mobility is such a good strategy.

Seems to me it is better for each star system to build mobile ship with good sensors to intercept all comers. But it seems the AI doesn't like to use fast ships. My ships are all speed 7 = 2 warp engines, and I have no problem intercepting and getting the first strike in all the battles.

There is no AI research order. The AI isn't scripted at all. Regardless I too thought why the AI was doign this, one ship makes sense but not 5 :/ Still they eventually built ships with weapons.