Mega Man 9

Galaxy Man - Use Mega Buster
Jewel Man - Use Black Hole Bomb
Plug Man - Use Jewel Satellite
Tornado Man - Use Plug Ball
Magma Man - Use Tornado Blow
Hornet Man - Use Magma Bazooka
Splash Woman - Use Hornet Chaser
Concrete Man - Use Laser Trident

Wall Shooters - Use Mega Buster
Giant Machine - Use Laser Trident*
Blob Monster - Use Black Hole Bomb
Dr. Wily #1 - Use Mega Buster
Dr. Wily #2 - Use Mega Buster
Dr. Wily #3 - Use Plug Ball**

* - The Laser Trident is the weakness of all three sections of this boss, but the middle section is made much, much easier by using the Tornado Blow on it.

** - The Plug Ball is the primary weakness of Wily's final form (the UFO). However, if he appears too high to attack with the Plug Ball, quickly switch over to the Hornet Chaser and use it on him. They will hit him high above for only one bar of energy per strike, but it will help you decrease his energy a little bit more.

On the first Dr. Wily stage, after the check point there are six pipes. Two of them have weak respawning enemies. Use Jewel Satellite and stand on top of the first set of pipes. You will occasionally get extra lives and a lot of bolts. You can use this trick to replenish lives lost from the puzzle that is up the ladder. This also helps when completing challenges. Note: This requires a lot of time.

You will need the Jewel Satellite in order to do this trick. In the beggining of Hornet Man's stage, move to the right until you reach the first ladder. Without destroying the potted plant robots, activate the shield and stand on the second platform in between both the robots. If you remain standing there, the missiles will be destroyed and the screws will automatically land on Mega Man. This also increase your kill count for your achievements.

To easily defeat the rock miniboss on Jewel Man’s stage, equip the Hornet Chaser. The Hornet Chaser, when deployed, will attack and damage the rock foe even when he’s on the ceiling, forcing him to come down where you can quickly finish him off.

To easily defeat the flame dragon miniboss on Magma Man’s stage and in Dr. Wily’s castle, consider equipping the Concrete Shot. Five shots to the face of the dragon with the Concrete Shot will quickly dispatch it. While the Black Hole Bomb will suck all of the flames off of the dragon’s body, rendering it unable to attack, it won’t heavily damage the dragon itself. Use the Concrete Shot instead.

Defeat five Robot Masters to get the Rush Jet Adapter from Roll and Auto.