DS Daily: Space available

Thanks to the Virtual Console, the Wii has become a haven for shooters. But the DS, with no Virtual Console, hasn't. There are very few original shmups on the DS, as well -- pretty much just the Nanostrays and Ketsui. We are of the opinion that any system that can handle a shooter -- which is any system -- should be loaded with them. This is especially true for a platform like the DS, which is both extremely cheap to develop for and ubiquitous. If a niche game is going to do well, it'll be on the DS.

So why hasn't the DS become a shooter's paradise? Is the screen gap really that much of a problem? Are shooters too hardcore? Or is there some other reason, do you think, that the DS has yet to fill up with shmups?