the reason i'm asking is i just got the power rangers game and i remmeber it as a kid having a hard case...and i seen some pictures of the box in auctions on ebay and it's a different box.
My US Power Ranger and my US Sonic 3D Blast have boxes too. Maybe it's more common for US games to have boxes instead of plastic cases.
I think that as a general rule, earlier Genesis games came in hard cases and later games came in cardboard boxes.
As far as I know, castlevania and contra had both box and plastic case. My guess is that the later games that had a plastic case switched to box on their 2nd run to save money on manufacturing cost. I will say though the boxes really sucked. Made of real cheap thin cardboard material that broke easily. The manuals were already getting bad at that point with them switching to fully b/w and using cheap printer like paper. The two combined are the most tackiest thing I have seen in history. I guess they figured at that time no one gave a shit about the manual or the box.
Kind of off-topic but... Cardboard boxes were one of those think that kept me away from collecting Nintendo stuff, no matter how well you treat them they allways get damaged, and the nintendo ones are... ugly, and all non standard. Each game has its title/logo/publisher in random places and just looked plain ugly on a shelf, specially GBA games
Majesco releases... In 1997, Majesco assumed manufacturing and distribution responsibility for the Genesis line from Sega in the US. At that time, they re-released several games which had previously been distributed in plastic cases, including the aforementioned Castlevania and Contra from Konami and quite a few first party Sega games. Besides the general quality of the cardboard box itself, the print quality was blurry and not that great in my experience. You're much better off trying to pick up the plastic box versions if given the choice.