The First Adventure Island
Adventure Island is a platformer released on the NES in the late 80s. It follows the character Master Higgins trying to rescue his girlfriend Tina from an evil witch doctor. Game play is pretty much your standard run from left to right through the stage with some twists. There are enemies as usual and they can be killed with weapons that are obtained from eggs throughout the level. There are 2 weapons and axe and some fireballs. The ax is pretty standard, throw it and it kills basic enemies. The fireballs are obtained from hidden eggs and can kill basic enemies along with boulders and rocks. You will play through 4 levels in an stage, and at the end of the 4th is a boss, which is a different form of the witch doctor. (and always the witch doctor)
There are a few things that make Adventure Island different from other platformers. The main detail is the stamina bar at the top of the screen. As you run, jump, throw weapons this bar will decrease, if it empties then you will die. This stamina bar is replenished throughout the level by picking up fruit (or milk). An element of strategy is added by this, as you cannot just run through the levels as fast as possible being as you must pick up some fruit. Another interesting feature is that if you already have a weapon and break an egg that would contain an axe, you will gain a skateboard. The skateboard will move faster and will not allow you to stop, however will allow you a free hit without dying.
The problem here is that much like the bosses, there is not much variety in the levels. There are water , cave, temple, forest, and mountain levels and that is about it. Literally every 4th level is the forest level. The game is very much worth playing however. The controls are simple with B attacking and A jumping. The difficulty is high but as long as you just keep pushing through it can be done. It is very important however to pick up the Bee secret item right before the end of the first level so you gain the ability to continue. After collecting the bee, just hold right and press start at the title screen allowing you to continue. To be honest the other two NES sequels are much better games(there are also 2 more on the SNES), but playing the original should be done first as the new features added in the following 2 games may spoil you. I highly recommend Adventure Island for the NES if you have determination and are up for a challenge.