Wonder Boy in Monster Land/Round 2

Part A

 * 1) As you begin to make your way to the right, you will encounter mushrooms.  The first time you kill them, they drop money.  The second time you kill them, they drop a point item.  Beyond that, they will not give you anything, so don't waste too much time fighting them.
 * 2) Ideally, you should try to reach around 90 gold in this section so that you can spend 40 on a Light Shield, and 50 on Cloth Shoes.  If you can't afford both, it is probably best to purchase the shield to avoid the arrow attacks shortly ahead.
 * 3) You don't need anything from the bar or the final shop, which sells special weapons.  Jump up to the platform over the water, and an hourglass should appear for you to collect before you lose another heart.
 * 4) Then jump down, and deal with the snake before an arrow hits you.  Turn around to face the arrows and block them with your shield.  Advance on the goblin that is firing the arrows and slay him before you enter the cave.

Part B

 * 1) Drop down to the bottom level of the cave to take out the snake.  When you see bats, approach cautiously, stop as soon as you see them begin to move, and stab them just before they make contact with you.  Bats typically leave hearts behind.
 * 2) As you begin to jump along the platforms over the lava, you will get a message when you reach the third platform (labeled "!" on the map).  You can push up to enter a secret door here, where you will receive a letter that you are to deliver in Baraboro.
 * 3) Beyond the platforms, you will arrive at door E.  Inside is a vampire which you must defeat in order to obtain the Broad Sword.  The vampire has two modes of attack; if you stand far away, the vampire fires a spread of fireballs at you.  If you get close, the vampire will make a dive attack very similar to the one used by Death.  Stay close enough to trigger the dive, but far enough away to safely stab him when he approaches.  When you defeat him, he will drop the sword.
 * 4) After you have obtained the sword, jump up the steps to exit the cave.

Part C

 * 1) Defeat the mushroom at the start and jump on to the platforms above the water.  When you reach the floating platform on the left, you can jump across to the right, where you will find another shoe store and a hospital.  Visit the shoe store if you were unable to purchase the Cloth Shoes earlier, and visit the hospital if you have less than three hearts.
 * 2) When you are ready to ride the floating platform to the top, be very careful when jumping off on to the platform occupied by the snake.  Try to swing your sword just as you are about to land so that you stab the snake before you hit it.  Then ride the floating platform on the left to the top (the ladder is only present in the SMS version of the game).  The small platform to the right of where you arrive has an hourglass for you to collect.
 * 3) Jump over to the laterally moving platform and ride it to the top of the cliff.  Deal with the goblin waiting at the top for you, and approach door H to fight the stage boss.

Boss
The Mushroom King is not a powerful boss, but he is difficult to fight. He will bounce non-stop across the floor of the room. The two best strategies to hit him are either to position yourself to the side of wherever you predict he will land, or to try to jump up and hit him while he is in mid-air. Either way, watch out for the mushrooms that he tosses into the room. Take some time every now and then to stab the mushrooms and clear out the clutter so that you have some room to move around. As with Death, be sure not to stand directly beneath him when you defeat him, or you will collect the key before you have a chance to collect any of the coins he drops.

Once you grab the key, simply head right to the gate at the end of the stage.

Arcade/PC Engine

 * From the start, wait for the mushroom and jump over, stay close to the edge of the first building next to the tree and when the mushroom returns from left side let it hit you and a 60+ coin appears.
 * From the door B platform, jump left to make a coin appear. Then jump back up, and jump right to make a money bag appear.
 * Inside the cave, jump right from the second step to make a coin appear.
 * Stand on the left side of the roof above door E to make three coins appear.
 * Jump from the top of the stairs to the right of door F, to the right to make a coin appear.
 * When you reach the top of part C, jump to the left to the cloud. Jump three times on the left side to make three coins appear.
 * Jump to the right side of the gate, and jump up to make a coin appear.

Sega Master System

 * From the door C platform, jump left to make a coin appear. Then jump back up, and jump right to make a money bag appear.
 * Jump above the middle, smaller cactus before the cave to make a coin appear.
 * Stand on the left side of the roof above door E to make three coins appear.
 * Jump at the bottom of the stairs to the right of door F, to the right to make a coin appear.
 * When you reach the top of part C, jump to the left to the cloud. Jump three times on the left side to make three coins appear.
 * Jump in front of the tree to the left of door H to make a coin appear.