It is really just a DLC to the game. You can play the original game just fine without this. It seems reasonable to give gamers a choice to pay for additional content if they think it is worth the value of what they have added. I don't think I would consider that a cash grab. If nothing was added and it was just a graphical update, then I would agree with you but 10 bucks for a new game mode and cut levels is okay if you're into the game. I personally have a backlog that I'm still working through so I'll wait to get caught up or if it drops in price to like 5 dollars or below to see what the new mode is about.