I suggest the remaining card to change with bone pillars + some bone cards,
cos we have 1 parasite deck but we have (18) parasites, so in case after some fights people will take from us dragons , devourers etc, will switch to duo decks, but only with 6 pillars we will not have the possibility to make 2-3 death+darkness decks
(that's just an idea, if anyone has something better , lets to his way)