Please note this is a thread for ALL of the games in the series, from the one with the black guy to the pinball game, all are welcomed here. For those who have been fufilling their destiny to be in a box all their life, Metroid is a game that well defines the genre of(and pretty much started) metroidvania. The genre itself describes nonlinear gameplay where you just screw around to get shit to find better shit. (or in the case of Other M, run around like a moron in a lava filled room until the big man says you can turn on your antiheat suit). For example, an area might not be accessible until you get double jump. Games like (obviously) metroid, castlevania, and cavestory all fall into the genre (and of course theres more, im just going with the two ive played and the other obvious example)
Games
Metroid (NES)
Metroid II, return of samus (GB)
Super Metroid (SNES)
Metroid fusion (GBA)
Metroid Prime (GC)
Metroid Zero Mission (GBA)
Metroid Prime 2 Echoes (GC)
Metroid Prime 3 Corruption (WII)
Metroid prime trilogy (pretty much a one disk game with all three of the primes with reworked glorious wiimote controls) (WII)
Other M(WII)
...Then theres also Pinball and Hunters, the oddballs of the group. (Both NDS)
If you havent ever played a metroid game, Super and Prime are both very good places to start.

Super metroid, Name me one time master chief took on a giant lava crocodile. Yeah, I thought so.If he actually did, I aplogize. Still would get his ass kicked by samus.

Metroid Fusion, Yeah, nightmare's one of my favorite bosses ever.