OK, so I've decided to post my thoughts about retro games in the retro threads, like a certain user on here. I'll also post a video if I can find one. First I'll start with the 1986 Namco classic, Rolling Thunder.
This game is a run and gun (sort of) where you play as a secret agent trying to save a girl. Whenever I first played this game on Namco Museum: Battle Collection, I was like, "Holy crap this game is hard!". It is a pretty difficult game. You can only take one or two hits which sucks. One unique feature about the game is the fact you can jump from floor to floor, and hiding in doors. I found that a unique concept and it adds an amount of strategy to the game. Even though the only powerup is a machine gun, it's effective if you use it effectively. You can get pretty good too if you memorize the stages in certain places. I also like the secret agent themed music. I think it fits the game very well and it's really good too. I just like this game, despite the difficulty. 
Here's a video:
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