Lately I spent some time with Contra, which was more fun in the end than I had initially thought.
I've tried Castlevania a number of times - I've beaten the game on Hard five times, using unlimited items four of those times (which makes a playthrough about 30 minutes, maybe less), and I have no idea what I might need to do. I'm thinking it's in the style of HoD where you need to have the right combination of items equipped, but there's only one slot for "equipping" things - you can put a food item, magic, or a subweapon there, and the main weapon slot should probably always have the Vampire Killer - I don't imagine killing Drac with the flame or leather whips is going to work.
What's bad is that the game threw in all those useless items which plague Igavania games; there's no reason why I should have a 12.5% or 33% health recovery item, none. The weapons are not only useless, but the descriptions have me scratching my head; the Lightning Hammer is described as "nearly indestructible" and the throwing axe is described as "able to cut through stone," although that just means it can go up through a floor. Of course, so can Desmond's head.
So I really don't know what to do, and I fear that I'd have to try killing Drac with every last item. That might not even work. After you defeat him his room is sealed off; I've tried throwing everything at that door to no avail.
There are actually not too many gaffes in the game - at least in the early version I downloaded. It's possible they have updated the game, but every time I try to check for updates to games with my phone it fails (although I can view the list to buy new ones, whee).
My major complaints with the game: terrible story and worthless cutscenes; Meteor often impacts on the ceiling above the room you're in, thus wasting your item; no invincibility time means you're juggled by enemies all the damn time; some enemy hitboxes are terrible.
There are plenty of great design decisions in the game, however, including the admittedly great keypad control scheme, automatic detection of music mode (also lacking a bug in Contra where music can go crazy or hang even after quitting the game, leaving your cell emitting a horrible long BRAAAAAAW noise), and it's a pretty ambitious game for roughly half a meg.