55c9zkkxx (40 HC), for one more user
16o1f7j1a (35 HC), for one more user

And some general use codes (25 HC each):
gifthulkhalloween 
trickortreat 
earnhulkcoins 
blackfriday 
newezcoins 
bitcoin 
enjoytheweekend 
gifthulktips 
surveycheckin 
ezcoinsmostpopular