23 Royal Rumble participants announced, 7 spots open.... who will take them?

I think nick f is wrong i think that christian is not going to be in the rumble but he will interfere in hardy's match as i think he is the one trying to take out hardy, therefore making a triple threat match for the wwe championship at wrestle mania, but then i think undertaker will win the rumble making a fatal four way match for the wwe championship at wrestle mania, as for the extra 7 i'm not sure but i think HBK will be one of them