What's a Metroidvania?

[alextfish]

Some people aren't familiar with the term I used in my last post, "Metroidvania". So I thought I'd give my definition of what kind of computer games count as in the Metroidvania genre. It's a somewhat fuzzy-edged category: I think a game can probably miss any one of these tests and still count.

• Platform game. Not an absolute requirement, but pretty close. I'd say Aquaria counts, but only because it's so clearly following all the other traits of Metroidvanias.
  
• Powerups granting new abilities (not just increased firepower or whatever). Upgrades to the height you can jump count, for example, or gaining the ability to destroy bits of scenery you couldn't before.
  
• Nonlinearity. Being able to revisit areas you've been to before, in order to collect things you missed or weren't able to reach first time round, or in order to find routes to new areas.
  
• Secrets! Many games have optional bonuses and hidden bits, but they're an absolute staple of the Metroidvania genre. The best games in this category have at least three different kinds of secret: for example, extra health, coins to spend on upgrades, and occasional new types of weapon or optional powerups that aren't required.
  
• Enemies and bosses to fight, and ranged weaponry. It's a slightly odd criterion to mention here, but many players do consider this a required part of the genre.
  

My game will meet all of these criteria.

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