This is the original Metroid game for the NES, I loved Super Metroid on the SNES, and felt like I should go back and finish the original. I’ve played it several times over the years, but have never gotten particularly far. The game is incredibly hard, and does not feature a map like the later sequels.
Whenever you start, or begin again after dying you only have 30 health. This means that you can end up spending quite a lot of time just trying to rebuild your health to full. This can take a lot of time later on when you have multiple energy tanks.
I kept finding that I would get stuck under platforms in lava. I was unable to turn into the ball, or to walk and so I was hammering buttons trying to get free whilst I lost most of my health.
Unlike in later games there are some upgrades which respawn. When you pickup either the ice or wave beams the other one will reappear allowing you to switch between them. This is important, since you need the ice beam to destroy the metroids at the end of the game. The wave beam however is very useful throughout most of the game, since you can’t angle your shots diagonally like in Super. It allows you to kill the enemies which are at your feet but below the line of your bullets. It also travels through platforms and walls, allowing you to hit things all over the screen.
There are so many secrets throughout the game, several of which are mandatory to complete it. I’m not sure how you would ever find a lot of them without guides or people showing you to be honest.