Cursed Castilla

Giant homage to Ghosts 'n Goblins with loads of spanish mythology sparkled on top make for a challenging game, that's still fair. The only draw back might be the ending stipulations, because you need to collect 5 hidden tear crystals, so you can get to the final level. The legendary hero ending has other stipulations, but those aren't mandatory, thankfully. You can also get the free version, which doesn't have two new stages and save system, over at Locomalito's website. Be prepared to die a lot.