Mega Man 6

Super password:
Enter B6 D4 F2 F4 F6 as a password to begin game play with all weapons and items and all levels completed.
Information in this section was contributed by ricky webster and Jake Taylor.

Beat helper:
Spell the word "BEAT" from letters found in four different stages to get an attack bird with an arsenal of weapons.
Information in this section was contributed by Jake Taylor.

An energy balancer can be found in Tomahawk Man's area. It is located towards the end of the level. When you have the option with two ladders to go up, take the ladder on the left. In the next screen, break the "breakable" box with a charged "Power Mega Man" attack while dangling from the ladder without falling into the spikes. The Energy Balancer will refill the lowest weapon you have automatically when you get a weapon capsule (unless you change into a specific weapon).
Information in this section was contributed by Jake Taylor.

Hint: Recommended order:
Information in this section was contributed by Alex Myers.

Flame Man
Blizzard Man
Plant Man
Tomahawk Man
Yamato Man
Knight Man
Centaur Man
Wind Man

Try the following order to battle the Bosses:

Flame Man
Plant Man
Knight Man
Centaur Man
Tomahawk Man
Yamato Man
Blizzard Man
Wind Man

The Plant Man stage will be difficult, but Plant Man himself is easy. When you defeat both Plant and Flame Man, you will receive their Rush Power and Jet upgrades. In the first part of your starting adventure of Dr. Wily's place, you will see a destroyable panel of glass to the right of the switching platforms you encounter in Wind Man's stage. To get there, power up on the floor where you climb the ladder and jump on the platform. Because the platform switches quickly, you must just barely jump on to the next platform and walk far enough to hit the panel with your powered-up blast. Once you get it, fall down on the very right part of the screen. You should land on the steel below in the other stage of the level. Once you destroy the panel, go back up the ladder and use the Rush Jet Adapter. Jump off the first platform on to the second, then drop below the second. Then, use the adapter quickly to just fly high enough to the edge of where the panel used to be without hitting the spikes. After that, there are only a few quick enemies to dispatch, then a block with four One-Ups inside it, and the end takes you directly to the Boss.
Information in this section was contributed by Ford4Me33.

Try the following order to battle the Bosses:

Knight Man
Centaur Man
Wind Man
Flame Man
Blizzard Man
Plant Man
Tomahawk Man
Yamato Man

This is recommended because Knight Man is fairly easy to defeat with the standard blaster. For each battle afterwards, the Boss is susceptible to the new power. For example, the weapon "KnightC." is powerful against Centaur Man, etc.
Information in this section was contributed by Jake Taylor.

Hint: Recommended weapons:
Bosses in later rounds (after all weapons are acquired) are susceptible to these weapons:
Information in this section was contributed by Jake Taylor.

Level 1: PlantB./F.Blast

Level 2: SilverT.

Level 3: Charged "normal" attack

Level 4 (Dr. Wily the first time): SilverT.

Level 5: Y.Spear/Charged "normal" attack

Level 6: KnightC.

Level 7: Each teleporter takes you to one of the original eight bosses. Starting in the upper left teleporter and moving clockwise: Blizzard Man, Fire Man, Tomahawk Man, Wind Man, Centaur Man, Knight Man, Plant Man, and Yamato Man.

Level 8 (Dr. Wily the second time): Combination of SilverT., KnightC., Y.Spear, F.Blast, and W.Storm

Hint: Finding hidden areas:
Most places or objects with obvious cracks (for example, boxes, stone walls, etc.) can be destroyed with a charged "Powerful" attack.
Information in this section was contributed by Jake Taylor.

Hint: Rush Power Adaptor (POW):
If you use it on Plant Man, you will alter his attack pattern. It makes him a bit more challenging.

You can use it on Yamato Man to slow him down. Hitting him with it makes him hesitate. If you hit him with it after he throws his spearhead at you (may require some practice), you can slow him enough to hit him three times before he can pick it up.

Using it on Centaur Man causes him to automatically charge you (most likely), although sometimes, he may just disappear.

If you use it on Wind Man, you can stop his wind fans from drawing you towards him. Wait for him to draw you in. When close enough, let him have a charged shot. If you hit him with a constant barrage of it, he may never even get the chance to use his wind fans or fire his blades.

Try using it on the two pods in the first Mr. X stage. It will keep them from being able to charge and hit you, and you are guaranteed to always hit them perfectly.

Glitch: Obtain weapons without fighting Bosses:
Enter the password to start out with only the energy balancer item. Go to a stage and bring up your weapons menu. Highlight the standard "M. Buster" bar and press Left or Right. You will hear the pointer move over, but "M. Buster" will remain highlighted. Go through the stage and pick up weapon energy capsules. You will hear them fill up weapon energy, even though you have no weapons yet. Defeat the Boss and go to another stage. Open your weapons menu, and you will have master weapons that you did not need to fight for. You may also have BEAT plates, yet the Boss you obtain them from may still have appeared on the stage selection screen.

Glitch: Keep punching:
Get to a screen and where you are about to scroll over to a new one (for example, when you find a mini-Boss or jump down one screen). Fire the Rush Power Adaptor as you scroll the screen over or down. It does not need to be charged. Mega Man will keep punching as you scroll.

Glitch: Misspelling:
After you defeat Mr. X, he says things about how Mega Man ruined his plans. At one point you can see that he says "My plans for destruction has faild." In one case, the word "plans" should be changed to "plan" to make the sentence correct. In another case, the word "has" should be changed to "have" to make the sentence correct.
Information in this section was contributed by MelloProto.