I'm in the process of developing a 2D action game. I've been a fan of many action games in my past (Tyrian, R-Type, Raptor, Gradius, etc.) If I knew how to post polls on this website, that is what I am intending. Just out of healthy curiosity - which do you prefer?:
Vertical- Games like Tyrian, Raptor, and Cybattler exhibit this. They seem to provide a much more superficial angle to the gameplay. DB games I've seen include Shift Break, Last Overkill (kinda repetitive), and something else I just can't remember.
Horizontal- Games like R-Type (good ol' R-Type), Gradius, and Last Resort are good examples. These games seem to have more "depth" in their environments and action. The only DB game that comes to mind is L-Type (a fun play on R-Type).
Oh, don't forget PS2 owners that R-Type Final is geared to air next month.
In giving an answer, please attempt to give a "reasonable reason". If you like Horizontal, say something like "Always loved R-Type", etc. But to speak for Vertical who can forget the honestly fun, colorful, and furious gameplay of Tyrian.
"I need gopher-chucks!!"