There's Aristocrat's group (vulture that lures in outcasts, unknown purpose as of yet), but since 
@Rooster_Tyranny is missing, that one's unavailable. There's the Resistance (mainly ravens), led by Shadow, who is against the pigeons but isn't that friendly towards crows (of course Molly and Storm wouldn't know that). And then there's Blizzard's flock, which is basically a peaceful mixed group of mostly pigeons and gulls that don't bother other birds but also don't fight the pigeon military. Cement's gang is another group, but it's all pigeons.
(Cement doesn't know Suliver's plan, but she guessed that he was up to something so is pretending to know it so he'll accidentally tell her what it is.)
Suliver continued to ignore Russet, but his thoughts didn't. 
My sister got herself a mate. He thought in disgust, 
Wish I could kill them both now.. but I do need more allies if I'm going to take on those other gangs that will be against me. 
"I thought you disapproved of my violent ways, sister." He cooed in a low, dangerous voice, so only Russet and Cement could hear. "Or is this a trick? If it is, you know that your flock will be crushed. And I will keep you alive to watch as I kill them one-by-one, starting by your limp-feathered mate." He spat, clicking his beak at the end of his threat.