Wily Capsule

Wily Capsule (ワイリーカプセル) is the teleporting saucer that Dr. Wily rides and uses for combat after the destruction of his Wily Machine. First appearing in Mega Man 4, it is the final form of Wily in said game and onward, which torments Mega Man for the rest of the classical series. It was at its strongest in Mega Man 7. In Mega Man 5 it's called "Wily Capsule II", in Mega Man 6 and 7 it's simply called "Wily Capsule", and in Mega Man 8 it's called "Wily Capsule Great" (ワイリーカプセルグレート).

Transport
Dr. Wily's spaceship transport doesn't has a official name, but is referred by fans as "Wily Capsule" and "Wily Saucer", and the latter name is more used to differ it from the machines used in boss fights. It first appeared in the first game with a red and yellow color, and the red color was changed to blue in Mega Man 2 to 7 and the Game Boy games. In Mega Man: Powered Up it's red and blue, and he uses it to kidnap the original "8" Robot Masters (including Time Man and Oil Man). He usually doesn't directly battle Mega Man using only the saucer, except for Mega Man IV (referred as Wily Capsule due to being a boss) and the ending of Mega Man V, but Wily attached it in most of his Wily Machines.

Megaman 4

 * In Mega Man 4, the Wily Capsule remains hidden, and attacks Mega Man with four swirling laser balls.

Megaman 5

 * In Mega Man 5, the Wily Capsule attacks much like in Mega Man 4, but it fades into sight before attacking Mega Man with four laser balls.

Megaman 6
In this game, it did pretty much the same thing as the others. Dr. Wily would constantly appear and disappear from time-to-time to to shoot about four projectiles in every direction. This Wily capsule had no specific weakness, so it was best to rely on the Mega Buster to defeat it.

Megaman 7

 * In Mega Man 7, the Wily Capsule disappears and reappears much like in Mega Man 5, but instead of fading in, it pulls off a "cloak" of sorts. It also attacks with 4 laser balls, but the laser balls have varying elements; ice, fire, and thunder. Also, the Wily Capsule might fire thunder balls that go across the floor.