Technically I've abandoned the Narukami comic--too many plot problems, not enough solutions--but I'm still really pleased with these boss designs. The idea lives on in concept art, at least!
Here's the spoiler for these three: whoever had a Curse Seal or any physical connection to Orochimaru's power would get cursed and turn into a boss monster for Amaterasu to fight. Anko gets combined with the Spider Queen, Kabuto has the misfortune of sharing part of his name with another boss (Crimson Helm = Akakabuto), and Sasuke is all special and sort-of original and turns into a Curse Seal Level 2 wolf-monster. I've got a color version of his design here: [link]
Kinda sad the idea fell apart before I could use these, but I can't carry an entire crossover comic plot on cool boss battles. :
\ Orochimaru himself had a pretty cool boss design--think Orochi but singular, with white armor--but I don't think I ever created a finished concept of him.