Ancient Minister
He is the servant of the main villain of the game but he turns to the good side as R.O.B.
Petey Piranha
Petey shows up within The Subspace Emissary. He carries two cages, one in each hand that contain Princess Zelda and Princess Peach. You only get to save one.
Rayquaza
Rayquaza appears in The Subspace Emissary's jungle section, when Diddy Kong finds Fox's ship crashed near a lake.
Its moves include the following things listed here.
It digs into the ground and attacks its foes.
It attacks with high speeds.
It has a variety of range attacks.
Ridley
The leader of the space pirates in the Metroid series, Ridley is a large, flying pterodactyl-like creature that can breath fire.
Porky
A monster terror spider that had a variety of attacks from attacking with its 8 legs to powerful energy cannons.
Galleom
A boss that transformes alot from its vehicle like mode to ram into foes and a superpowerful stomping robot.
Meta-Ridley
Same as before only made of metal and will attack Captain Falcons ship with several attacks.
Duron
The second of the two Subspace Army mechs. After the Mr. Game & Watches are tossed out of the control room of the Battleship Halberd, they are converted into Shadow Bugs. These Shadow Bugs combine to form Duon, fought as Fox, Peach, Zelda, Lucario, Snake, and Falco. When it is defeated, it reforms back into a single Mr. Game & Watch, which joins the effort to defeat the Subspace Army. Expect this boss to be a hard one.
Tabuu
Tabuu is the main villain of the game. He has a blue-fluorescent color and a real human shape.
He turned every Character into a trophy but Kirby escaped it with a badge. He was about to do it again but Sonic stopped it from doing it.
Expect him to be a hard foe because he is the last boss but luckily you will be able to be almost everyone(Even villians and heros) and have six characters selection(Choose those 6 characters wisely).