When players first delved into the world of Metroid on the NES, they had no idea that they were playing as a woman throughout their entire journey through the desolate world of Planet Zebes. Why? Because it didn't matter! Samus is able to take out Kraid, Ridley, the resident Metroids and Mother Brain single-handedly.
The big reveal comes at the end of the journey, only if the player completes the game in 3 hours or less. Samus carries the illustrious honor of being one of the bravest protagonists of all time, shattering the supposed trope of damsel in distress!
All of the possible endings for Metroid can be viewed here.