Donkey Kong Jr./Walkthrough

Vines Stage
Junior starts out in the lower left corner and must make his way to the vines on the far right side of the screen before crossing over the branch back to the left.

Junior must grab one of the three vines above him, and climb up to one of the two ledges to his right. He can jump to the next vine from either ledge, where he must fall down to the tree top below.
 * Starting out

Carefully jump right from one vine to the next before grabbing the fourth vine from the right. Climb up above the right ledge and maneuver Junior over to the far right vines. Climb up and on to the branch above. Jump over any Snapjaws that pose a threat and leap up to the higher section of the branch before leaping for the key and ending the stage.

Along the way, the pear and apple fruit prizes can be plucked with ease. If you have time, it pays to eliminate any of the Red Snapjaws since they won't come back. The banana is in a precarious position and should only be plucked if time and safety permits.
 * Fruit

Springboard Stage
NOTE: The US version omits this stage in L1 and L3.
 * This stage earns its name by hosting a springboard at the bottom of the screen. Its purpose is to provide Junior with a shortcut.
 * Ordinarily, Junior must jump on the springboard to reach the treetop on the opposite side. Then he must ride the moving platform to the right and climb up the chains beneath the pulley. He must step on to a ledge which is placed directly beneath the point that Small Nitpickers like to lay eggs, so watch out. Then he must jump to the left to reach the first hold. When the small platform is beneath him, he must drop down and let it carry him to the next hold which rises and falls.
 * If Junior uses the springboard as a shortcut, he can move directly from the start to this small ledge by pressing the jump button at precisely the moment when he hits the springboard, and he will launch up to the small platform immediately.
 * Junior can only jump up and grab the second hold when it is in its lowest position. Once he safely has it, he must reach left and grab the chains that extend below Papa. After pulling himself up, he must navigate through the gauntlet of small nitpickers to reach the chains on the right side, where he must climb up a little further to reach the branch. Jumping over the gap in the branch and timing his jumps to ensure that he doesn't collide with any Small Nitpickers, he can reach the key and end the stage.

Mario's Hideout
NOTE: The US version omits this stage in L1 and L2.
 * The layout of this electrically filled chamber is substantially simpler than the previous stages, but it poses an even greater threat. Not only are Sparks a danger to Junior's feet on the ground, but they also pose a danger when they pass over head. A nervous player may anxiously jump over a spark only to realize too late that a spark was headed Junior's way above him.
 * The route is simple, from the start, cross over to the right, climb up, cross back over to the left, climb up, cross once more to the right, climb up again, and finally back to the left in an effort to reach the key.
 * While the Red Sparks remain in their loops, the Blue Sparks move from the top of the screen to the bottom, taking the blue vertical pathways along the way. In the beginning, the Blue Spark will randomly choose one of the four pathways beneath Mario, so cross below Mario with care.
 * The fruit are easily plucked on each level, but nailing Sparks with them will take extra timing, and may put you in a bad position if you're not aware of your surroundings.

Chains Stage

 * This is Junior's last chance to save his father, so it's now or never. Donkey Kong's cage is positioned above a set of locks, and the keys to those locks are located on chains directly below them. All Junior has to do is push those keys up in to the locks and grant Donkey Kong his freedom.
 * Blocking his way will be stubborn Red Snapjaws and Large Nitpickers that Mario sends after Junior. The Large Nitpickers will fly from one end of the screen to the other before swooping down a level and reversing direction.
 * Obviously it is faster for junior to push up keys two at a time when the chance is available, but that exposes Junior to twice the danger as Red Snapjaws could be located on either chain at any given moment. So proceed with caution, and try to save the apples for the moments when the Red Snapjaws are located beneath them and can be done away with for bonus points.
 * Once Junior unlocks every lock, Donkey Kong will come tumbling down and mighty Junior will catch him before the game starts all over again from the Vines Stage at a more difficult level.