Rambo (NES)/Knife-only

This game is already quite challenging. However, if for some reason you want to make the game much harder, you can try beating it using only your knife as a weapon (with one exception - grenades, for the last boss). Playing Rambo in this manner is very challenging, but if you can tough it out, the satisfaction of overcoming such a challenge may make it worth your while.

Game functions
Essentially, everything in Rambo can be geometrically measured in units; you will understand this after a short time of playing. John Rambo stands a little more than two units tall (or a little more than one, if he kneels), so that any enemy attack between where he stands and three units above that (or two, when kneeling) can harm him. An attack with Rambo's combat knife has a range of one unit forward, in the column either two units above where he stands, or one unit above where he's kneeling.
 * Units

Timing is important. Rambo can attack with his knife about 1.5 times per second. Additionally, an attack isn't immediately effective, but takes a fraction of a second to strike the enemy for damage. Timing is especially important for enemies that fly toward Rambo.
 * Timing

Your combat knife is the most powerful weapon in the game, able to kill any non-boss enemy in one, sometimes two, strikes. Using only your combat knife, though, it is best to deal with only one enemy at any one time.
 * The knife

Checkpoints must be used wisely in Rambo. When you die and choose to "continue," you will return to the last place and situation where you talked to someone - your checkpoint. During a conversation, you can also press and copy the password it gives you to return to that checkpoint. Although having plenty of life is important throughout the game, it is especially important to have good health at checkpoints.
 * Checkpoints

Finally, if you want to make the knife only game less difficult, then allowing yourself to use throwing knives as well as your combat knife will make things much, much easier. The power of your throwing knives will increase with your level, so if you use them, leveling is important.
 * Throwing knife

General tips

 * Both life and medicine are precious and rare, especially fighting with only your knife. Try not to lose too much of either.
 * Beat every boss you can for hearts, which give you extra life. Try to start a battle with a boss with nearly full life.  Try not to bother yourself with using medicine during the fight.  Fight them wildly, and don't worry about your life.  One of you will eventually die, and it will almost always be him.
 * At the first mountain area (the one with falling boulders, at which you arrive in the process of getting to your helicopter), there is an ape to the right of the S square which can be easily killed for some medicine. Do that a lot to get lots of medicine.  You'll need it.
 * Once you beat the fireball machine, go right one area (to the area with the spike balls), and get into that building. Go one room left, use the S square in that room, jump down to the bottom level, us the N square to the left, and then go left to the boss.  Don't worry too much about damage in traveling from the fireball machine boss to the next boss ahead--a boss battle will be coming up, and it will be 100% easy and safe.  Enter the room to the furthest left of lower level of that room, and the boss battle for the keys will begin.

Defeating specific enemies
If you can, don't bother with them. They aren't worth it. Their jumping makes it difficult to determine whether to stand or kneel while attacking, and their speed makes timing difficult. If you must attack, remember: strike early.
 * Tigers

These are usually worth killing. First, you can stand at ground level, stand still, wait for it to fly by, jump up, and strike it. This method requires precise timing. Another method is to stand three units above ground level, and wait for the ghost head to fly by you. This is easier, but requires a platform. Try not to get hit by these (both methods of killing them are 100% safe, so long as you don't mess up); they cause a lot of damage.
 * Ghost Heads

You should only attack the big spider if you have at least 80 health. A good way to get into the cave and to the spider with that much health without using medicine is to rescue the kid first, leave the cave without killing the spider, bring him home, and his home will be a free rest area. To kill the spider, you should go to the left of the spider, stand a unit and a half in front of it, and keep striking it until it dies. Doing things in this manner, you shouldn't have to use medicine.
 * The Big Spider

Don't bother with them if you don't have to.
 * Fish

Best avoided. If you must attack, attack low.
 * Big Birds

When they get close to you, they will attempt a jump kick. Their kick will cancel out your knife attack, and will hurt you a lot. To kill them, let them get about two units away, and let them try to attack. When they try this, run a few units away, let them land, then turn around, and attack. The orange ones won't kick unless you are almost a unit away, which is their kicking range. Allow them to chase you, at a distance of about 1.5 units away from you, until they kick. Then, let them land, turn, and kill.
 * Teal/Blue/Orange Kicking Soldiers

You can avoid their fire by ducking. They attack at a predictable, slow frequency, and killing them is a breeze. Don't mess up, though, or they'll hurt you bad.
 * Teal/Blue/Camoflauged/Pink/Green Shooting Soldiers

Let them come to you. They strike at regular intervals - strike them just before they are able to strike you.
 * Big Men With Big Clubs

You cannot kneel to dodge their bullets. The best thing to do for them is to lure them near the boat, stand on the boat (where they can't hurt you), kneel, and stab them. You can also stand in the water, wait for them to fire, jump toward them over their bullet, and then quickly kill them. Remember that the best thing to do is deal with one at a time.
 * Traitors at Boat

You will meet the guards immediately after Co helps Rambo escape imprisonment. You cannot kneel to dodge their bullets. You must try hard to deal with only one of them at a time. They are much like the Traitors, and shoot at regular intervals, but they can jump, so you can't just attack them from a higher platform in safety. Try to let them shoot, jump toward them over their bullet, and then kill them quickly.
 * Orange Guards, Rocket Launcher Guards

They will throw grenades at you when you are a few units away. Let them throw, run away from their grenades, then run back and stab them.
 * Grenade Throwers

Start the battle with at least 200 life, preferably more - then you don't have to bother with medicine. Aim low as he comes toward you, and strike at him like crazy. You will almost die, but if you do it right you won't. After this battle, just run to town (two areas to the right), running away from any enemies. These enemies can't be safely beaten with your combat knife. At town, you can rest to make up for any damage received.
 * Motorcycle Boss

Get rid of falling spikes to left and right of the S square. The tiger is to the left of it; lure it over to the S square area, and then continue in one of the following ways:
 * Fire Tiger
 * 1) If using throwing knives, just go in with life as full as possible (preferably above 300), and throw knives at it like crazy until you win.
 * 2) If using the combat knife, go in with life as full as possible. Keep striking in the direction of the tiger as it runs through you (face it as it runs through, and then turn around when it's on the other side).  Every time it runs through you twice, check your life. If it's below 100, heal.  If you have no medicine when you go in, you'll just have to use throwing knives.

Before you start, make sure your health is above 400, and ignore your life for the rest of the battle. Destroy the gate to get through, and stay on the ground the whole time (no jumping or climbing). Continually attack the machine. If a pink guy tries to attack you while you do this, kill him off and quickly continue killing the machine. Again, stay on the ground. Fight furiously enough, and you'll win with plenty of life to spare.
 * Flying Fireball Machine Boss

You can't kill it while it's jumping around. When it lands and stays still, destroy it with your combat knife.
 * Spike Ball

He is easy to beat with your combat knife. Just cut boxes in front of you like so:
 * Yashin (boss)

RS R#  ##

...with intact boxes shown as #, stand at R, and stab at S as Yashin approaches.

They will stand to shoot if you stand, and duck to shoot if you kneel. Just treat them like you did the orange guards. You can also stand on a platform two units above where they stand, kneel (so they shoot too low to hurt you), wait for them to come, and kill them.
 * Blue Camouflaged Soldiers

They just walk forward, and shoot at regular intervals. You can stand two units above where they stand, wait for them to come, kneel, and stab them in the head.
 * Men With Flamethrowers

Since you're already using the grenades for the boss, just use them for everyone. Occasionally, an enemy will jump in to try to kill you from either the left or right, the former having grenades, and the latter having arrows (useless). Kill them both with grenades whenever you can, to cut down on the confusion that will almost certainly result from trying to switch weapons. When both men are dead, throw your grenades at the helicopter until you have three left - save those for the soldiers. This is one of the few boss battles where you should keep an eye on your life. Whenever it reaches 200, heal if you can. This is a tough battle, so enjoy your victory.
 * Helicopter