It is a seperate "micro" expansion that you have to download from Impulse. It costs $10, but it seems many people think it is well worth the cost (much like the Entrenchment micro expansion, which I think is required to run this too).

wait... just envoy cruisers? not to sound weird or anything but... it doesn't sound fearsome or destructive...  unless they have some good firepower built in their hulls... lol

any other offensive unit/s?

Hmmm, i bought Diplomecy yesterday, but it doesn't show up on Impulse. Do i have to wait till 9.Feb?

EDIT:

Sorry, forget it. I see it right now. Damn, i'm blind...

It is improved, an overall better job of ship building (though still not optimal but that is very much a fluid thing and AI doesn't do fluid very well), better spending on research (AI actually can research the DS research tree, it gets nasty then) and better attack plans(I've had them throw different two fleets at me in a short span of time (1v1) so I had just finished off one and then the other gets me. OUCH!)

Thanks IC and SD! Loving Diplomacy!

It still has no problems screwing me at the last second as always.

many thanks. nice treat. keep being awesome guys.