Black Hole Bomb

Black Hole Bomb (ブラックホールボム) is the special weapon Mega Man and Proto Man get from Galaxy Man in Mega Man 9. It creates a black hole that pulls nearby enemies and enemy fire to it. It can also be controlled by the user via the d-pad and opened (detonate) up by pressing the fire button again. The Black Hole Bomb is Jewel Man's weakness, dealing about seven units of damage and also sucking in his Jewel Satellite. The Black Hole Bomb remains on screen for quite some time, which is most useful against Jewel Man, as positioning it just right will cause him to get hit by it multiple times with a single shot.

Attack power
The weapon deals four units of damage (excluding weaknesses and immunities) to large enemies that cannot be sucked into the black hole. Those who are sucked into the black hole are defeated instantly.

Capacity
It takes four weapon energy units per Black Hole Bomb. Mega Man can fire up to seven Black Hole Bombs with a full weapon energy gauge.

Usefulness

 * Black Hole Bomb can absorb almost any small or medium-sized enemy, regardless of if they're invulnerable to the Mega Buster or have their shields on.
 * The bomb can be used to destroy minions summoned by bosses, limiting distractions created by Splash Woman and Hornet Man.
 * It sucks in almost any projectile, including the ones shot by many bosses like the Wily Machine and Wily Capsule.

Exploit
Since only one Black Hole Bomb can be on the screen at once, and bosses have a temporary immunity after being damaged, it's possible to cancel the current Black Hole Bomb deployed and disable the boss's immunity by accessing the "Start" menu. This will allow the player to defeat certain bosses much faster, such as Jewel Man and the Twin Devil.