Stealth, and Intelligence is all you need
You play as Solid Snake in the year 19XX, looking for captured Fox Hound members and seek out the Metal Gear. In this game you will use stealth get get by your enemies, and fighting will get you caught and set off an alarm. You will go screen by screen finding items in different places, gathering level coded key cards to access doors. Also gather weapons of unique kinds, nut having to use your bullets wisely, as they come in small quantities. Using silence is usually the best and/or only approach to advance through the game. You will have to find many secrets using the items found in the game, and think logically of what do do to get to new places.
The control is pretty much executed very well, and computer AI is very good for 1987. Boss fights occur throughout th game, which can be fairly tough. You will probably die a fair amount going through this game, but it is very fun and keeps you thinking all of the time. As well, the story is the beginning of the Solid Snake area.
This game is very well done and approached, and can be very challenging making you use your mind, but suggest you play it, may seem a bit dated nowadays.