It is immune to freezing - It is immune to less effects that towers and upgrades have.
It moves twice as fast as a Red Bloon, and faster than a Black.
They are encountered later in the games.
It could be said that the Black Bloon was formerly more powerful than the White Bloon, and thus was once the most powerful Bloon. In BTD1, only Bombs could pop frozen Bloons, so you needed bombs to have any use for Ice Towers. Also, since BTD1 does not have Snap Freeze, the Ice Tower could not deal damage. Because of this, more people used Bombs back then, and thus more people were affected by the Black Bloon's immunity to explosions.
In BTD3 and BTD4, a single pile of Road Spikes can almost take down an entire Black Bloon, leaving only a Red Bloon. In BTD5, one spike pile can pop a Black Bloon whole.
It is sometimes confused with the Bomb Bloon. Both deal with Bombs in some way.
In BTD1 and BTD2, because of its resistance to bombs, it is impossible to win the game using only Bomb Towers. In BTD3, BTD4 and BTD5, it is possible because of the Frag Bombs upgrade, and also, in BTD5, the Bloon Impact upgrade.
Strangely, Black (and also White) Bloons are small, yet containing two larger (Pink) Bloons.
In Bloons Tower Defense 6, Cluster bombs is considered a downgrade at times because of the fact that Cluster bombs and Bloon impact are in seperate paths with Recursive Cluster not being able to pop blacks.
In BTD1, Black Bloons can not be popped at all while frozen because they are immune to Bombs, while frozen Bloons are immune to everything except Bombs, this makes it more powerful than the white bloon at times.