I think Galyxx would probably want to be a part of Group Three, but Torahime would certainly be up for Group Two.  Leading an open raid on Shendilavri will likely lead to a chance to cross swords with some of Malcanthet's Radiant Sisters, which should be an interesting fight.  Torahime working alongside Echidna would probably be the best option there, since one's a lawful succubus and the other's a baatezu without any formal position in the hierarchy of the Nine Hells.<br/><br/>Methu and Ungrath could actually probably work fairly well in Group One.  Malcanthet has no love for Graz'zt, and Graz'zt has essentially formally allied with the night hag covey that wants to see Ungrath destroyed, so they do have valid reasons for seeking out an alliance of some sort with her.