Do not play alone!
Graphically the game is a mixed bag, the art and animation has all been ripped from the DS games they where native to and they still look as impressive as they did back then, however in HD they tend to show up a little more pixel than youd expect. The backgrounds are well detailed and the boss encounters suffer from the same issue as the main sprites, i guess it all comes down to how much you like tradional sprites.
The music is a joy to behold, many of the old Castlevania themes you remember from previous games return but this time they have been mixed into a heavey metal version of the tune, this has often worked well on previous titles in the series and works well here too. The assorted creature and player grunts are all functional and theres the option to change the voices to Japanese which is nice.
The game will literally last you as long as you want it to, if you can get a group of friends together the game could easily last you weeks, each person has a natural preference to a character and as you play your character will level up and collect new loot to equip making everyone valuable to the experiance. On the other hand if you are a solo player you may want to consider avoiding this game as once you have finished the game there is nothing to see beyond that. There is no story, no explaination as to why all of the assorted hunters are here so it will become very empty and lonely very fast. All in all id recommend tihs game to anyone looking for a good multiplayer platformer and even weeks after release im still going back for just one more shot.