The Iota Coalition is a joke. There's no secret there so don't worry that Evolution will read this and take heart. There are half a dozen alliances that have taken cities from Evolution in the last month. Interestingly enough, most of those same alliances don't lose cities to Evolution. Kind of hard to say the reason is because Evolution isn't in the area. I am pretty sure Evolution would really like to have a few Death Crusader cities to offset all those losses.
Most of the biggest advocates of the Iota Coalition are either nonentities or farms to acquire more cities easily. I am pretty sure Death Crusaders, Slaughterers, Atlantic League and Little Brothers don't even bother with the fiction of the coalition anymore. Some alliances notionally in the coalition bear a striking resemblance to The Olympians which might as well have been the Corps of Engineers for Evolution; building cities that fell so easily to Evolution that it fuels their growth far too easily.
As to attacks on alliances in the Iota Coalition, the most prevalent is hunting down of refugees from Evolution. This is a war to the knife; if you don't get that, refer back to the "going to conquer the world" mandate of Evolution. There is no safe haven for Evolution players who flee under attack. Evolution drops their players at the first sign of trouble; it would have twice the number of city losses if it didn't drop them. They're also happy to invite them back into the fold. Ergo, no jumping to an alliance of convenience to avoid the storm. The only way out for an Evolution player is to hold against the attacks (assuming Evolution will back them), go into vacation mode or enjoy how much simpler it is to play with fewer cities.
The war against Evolution goes just fine without the Iota Coalition. I am pretty sure no one is even copying memos to them when a city is taken. Personally, I've tried coordinating with nominal members of the coalition (despite the fact that people tell me it's a waste of time). Those efforts result in lots of talking and nonexistent doing. I really WANT to work with more alliances and get them involved and integrated in both offense and defense. However, that isn't happening and it's not from lack of trying. It's more a lack of interest in doing more than talking about standing together against Evo. As a result, there are forces banded together against Evo but it certainly isn't called the Iotan Coalition. In fact, it isn't called anything; the member alliances were too busy doing to spend time thinking of a catchy name. I'd send biremes across 3 oceans if Crusaders or Little Brother asked and have seen them do that exact thing. I can't even get alliances in the coalition and right next door to me to do more than think about something.