CrystalShadow said:
To me the core of the gameplay style is basically Freely explorable world with the bounds defined by the character's abilities.
(Which increase over time depending on new items or whatever else the setting can come up with.)
Basically, an environment where you can go anywhere you like, but some parts appear to be blocked off until you gain a new ability.
(Which is where the progression comes in. It's not progression in the sense that most RPG's use it. It's progression in the sense that you literally gain entirely new abilities that let you do new things)
Actually, come to think of it, there's at least some degree of overlap with how Zelda functions in terms of gameplay mechanics...
No. Its not about the 2D. Call me crazy but...
Actually believe it or not Dark Souls is a Metroidvania (Yahtzee supports this idea watch his Dark Souls vid). Its not about the abilities either its how the game's world is linked together. In Dark Souls you don't have special powers to reach areas either, you must trigger certain cut scenes to open up more dungeons and proceed, also the master key links dungeons together.
Want another example of a Metroidvania game?
Banjo Tooie all the worlds ("dungeons") can be linked together via secret switches that open passages to each other. Although this game also has an over-world.
Metroidvania is in the level design for the most part, in that its somewhat linear but at the same time it is "open". Its the illusion of an open world in a linear level design with alternative passages that connect different levels. And how you link em? With anything you please, key items, ability moves (like you said), cut scene/event trigger, etc.
I consider Metroidvania to be one of the best approaches to level design because you don't have the emptiness/lack of content of the open worlds.
Example: https://www.youtube.com/watch?v=fiCB8ycl8QI