At first I was filled with dread seeing their attacks of 20+, which is a bit higher than the piddly 1s and 2s the torians and I were trading shots with. Needless to say that all ship movement was stopped and all startbases and ships destroyed. Then I decided this would be a fun new challange

Here is an interesting and -eventually- dissapointing consequence. When races military ratings drop near 0 they become very very docile and paniky. After throwing our race into research I was finally able to drive the pirates out of 1/3 of my empire (at a cost) and hold it. Now that I even had something of a military the Torians were willing to give away the kitchen sink for peace - even though there was no way I could get to them for many many many more turns.

Then - the drengin declared war on the Altarans and Iconians - who are across the immensie galaxy (seriously - its me, the acreans, torians and eleventy billion pirates between them). The altarans and Iconains with a combined military rating of 1 decided within a few turns it would be better for them if they just surrendered - I mean in a few decades the drengin might be half way there. Better to surrender now. I mean the Drengin have a rating of 5! (their ships never last long against the pirates)

The drengin slightly later - no doubt embolden by a new military rating of 8 - then declare war on the thalans - who surrender to me, and then the acreans, who surrender to me.

To be honest, as the only civ left with any kind of working military and the sudden aquisition of 1/4 of the habitable planets (bringing my total up to between 3/5 and 3/4) I quickly lost interest in this particular game

Overall I would say the AI does not seem to handle the Pirates event well. They surrendered way to easily. There is no way the Drengin could have gotten a ship over to those civs to do anything so there was no reason to surrender