i formed an alliance pretty early in the game (first 45 min i think) on a 29 planet, single-star map.
what i did was, after scouting the best expansion route and finding an ai core planet along the way, i rushed a marza and some cobalts and just kept pressure on that system. lucky for me, the flank of my prime planet was the same ai that was asking me to attack this ai..
when i got to 40-60% i ceased fired and est. trade alliance
destroyed more units/structures and eventually got 100%, then peaced it out.. after that, the ai was asking me for all kinds of junk, like share vision, planet vision, backup..
never backed the ai up.. i think i dropped one mission and my % went down to 81.. completed the next, which was more units/structures on my enemy front, got back to 100.
POINT: it's nice to have a ceasefire/peace treaty not for backup.. but to eliminate that threat for the time being, while i tech and mass up my empire.. eventually we'll have it out.. but maintaining an ally is valuable to expansion.
on the other hand, I CANT WAIT until i get to jump a fleet to my ally's prime system and stick that nuke-tipped brutus knife in deep!
am i a bad person? nvm, dont answer.
ok, well i did it... kinda.
after squeezing the life out of the other two ai and my peace treaty still in place, we destroyed the last enemy ai's outpost and we got victory together.. after i allied with the ai in the beginning my alliance didnt go below 81.. i researched diplomats and it helped, i think.
when u win together, ur ai ally automatically breaks the peace.. and the victory screen asks if u want to quit of keep playing
i kept playing just to check some stuff out, and although my % was still 100, i couldnt even get a cease fire agreement and i lost all ship and planet vision..
so i guess thats it.. it may be more sophisticated to manage on a multistar map, but it was interested to test out an
achieved ally victory