Mostly so I have things clear, how is... The incapacity to die unless something really drastic is done handled here? I assume that the General would blow them to pieces or something, the kind of shit that makes everyone say "no way anyone survived that". But what about the rest?

As I mentioned when I apped Ikki, his "immortality" is a bit tricky, it has been showed him dying and resurrecting minutes after it or a few hours or days later. But also it has been shown that sometimes it takes longer for it to happen, back then it was said that so long as nothing like what I mentioned above is done the resurrecting thing would go on. But I would like confirmation on that and if it would work during the battle -again, no against the General as I do assume he would do something capable to kill anyone and everyone on first move basis-.

Also, Ikki will mostly hang around alone I suppose. Lone wolf and what not unless he ends meeting and sticking together someone else.