I'm currently playing a game as a custom race in an immense galaxy. The setting is painfull, 9 races...
Let me preface this post with the disclaimer that I had Ctrl-N'd about a thousand times, and I don't know if the bug that makes the AI still gets set down to mind-boggliningly stupid is still present...
Anyway, the Korath were on the same side of the map as me, and I make it my policy to kill those buggers off as soon as possible. I hate them, and their spore ships. So I declared war, and launch an offensive...
They are behaving in an exceedingly stupid manner. They've reaserched out to Graviton Driver III, but they don't seem to have developed any invasion technologies, spore or mundane. Neither have they made any use of engine technology, which means all of their ships have movement ratings of 2. Sure they've got enough firepower in a single ship to level one of my woefully under-armed fleets. Furthermore, they're using their 25-MD/5 Shield medium sized heavy-gunners in fleets, and leaving their planets guarded with with attack 4, defense 0 ships. I sat and watched as one of these ships was produced by a planet, launched, and proceeded to go the opposite direction of my dinky little fleet of 10 Laser/ 0 Defense and a host of transports sitting just in striking range of the planet. It left a a dinky 4/0 8 HP ship to defend.
I usually develop engine technologies, but don't equip many ships with them to avoid the 'you-can't-use-warp' mega-event, but even so my ships have a speed of about 7 (due to racial bonuses, etc). Needless to say, even though they have superior firepower and a huge technological lead, due to their incredibly stupid behavior I've managed to 'hit and run' their defenses into oblivion and totally overrun them with my soldiering tech.
I've never had an AI behave this badly at this setting. I have to confess that it's kinda fun, though... In the same way that it's kinda fun to use a laser pointer to trick a puppy into running head-first into a wall. Repeatedly. Poor, poor Krindar... did that hurt your snout? Oh what's that? Over there! Go get it! Get it boy!