Boom Boo

The Boom Boo (ブーブ) is an enemy that appears in Sonic Adventure 2, its remake Sonic Adventure 2: Battle and Sonic Lost World. They are large ghosts and servants of King Boom Boo who roam haunted areas. The Boom Boos are essentially large Boos who can shrink down when successfully attacked.

Appearance
The Boom Boos look like a normal type Boo, meaning they have white body round shaped bodies with thin hands and two small sharp ends below their body. Also they have black soulless eyes and a closed linear mouth which looks like it is knitted up. However, the Boom Boos are about three times larger than the regular Boos.

When shrunk down in Sonic Adventure 2, the Boom Boos' appearance changes to that of an attack type Boo. As such, they gain red and orange colored maniac eyes with black pupils and their mouth opens, revealing black sharp teeth. They also gain three points on their hands and the two ends below their body are transformed into one.

Powers and Abilities
The Boom Boos have the ability to levitate and move through midair. Also, when they take damage, the Boom Boo will shrink down a size instead of evaporating. However, they can only shrink down to a certain size before another attack will defeat them.

Sonic Adventure 2
The Boom Boos first appeared in Sonic Adventure 2 and later in its remake, Sonic Adventure 2: Battle. They can be found in the following Stages for each character:

In gameplay, the Boom Boos only means of attacking the player is by slowly moving towards the playable character when in sight. When making contact however, they cause damage. To defeat a Boom Boo, it must be attacked three times: hitting it once will cause it to shrink down to a large attack type Boo, hitting it twice will turn it into a regular attack type Boo and hitting it a third time will defeat it. Defeating a Boom Boo will award the player with 300 points. It should be noted that hitting Boom Boos with thrown objects will not affect them.

Sonic Lost World
The Boom Boos' next appearance was in the Wii U version of Sonic Lost World. In this game, they can only be encountered in Sky Road Zone 4.

In this game, the Boom Boos cannot be attacked and they will only fly around the Zone in large and straight rows with or without regular Boos, making them function more like obstacles. When touching a Boom Boo, however, Sonic will take damage.