"Tabuu's Revenge:Space-Time Chaos" is the adventure mode for Super Smash Bros. Max. It's designed as a direct sequel to The Subspace Emissary and is the first adventure mode in the series to include all playable characters in the main storyline. It's also the first advenure mode to include dialog as many elements of the game have in-game explanations.
The adventure begins as Bowser, who is in fact loyal to the Master Hand, receives an anonymous message that the Master Hand is still alive in subspace. the message also reveals that there are members of R.O.B.'s kind still alive in subspace also. R.O.B. and Bowser proceed to team up and find a way to journey into subspace to rescue the master hand the other R.O.B.s. Meanwhile, Bowser orders his son, Bowser Jr., to find and recruit fighters to go into subspace and aid Bowser and R.O.B. in their respective missions. After several failed attempts to build a subspace, the Crazy Hand volunteers himself as a power source for the subspace portal, the portal is finally a success.
Bowser orders Bowser Jr. to stay behind and help the explorers to get back home. Soon after entering subspace, the explorers(known in the planning stages as Group A) are attacked by groups of from various games including Eggman's Robots and even five different species of Shadow Pokemon(which look just like regular Pokemon except that their color scheme is the same as the false fighters from "The Subspace Emissary"). This is your first level and none the explorers in Group A will join your party. After battling the enemies, Group A encounters something that can't possibly be true, Tabuu who everyone was certain had perished at the end of "The Subspace Emissary". Tabuu then proceeds to turn everyone into trophies.
Back in Smash World, Bowser Jr. realizes that he has lost contact with his father and decides to put together another group of explorers(known as Group B) to go in after Bowser and the others. Before leaving, Crazy Hand gives Bowser Jr. a Smash Ball, claiming that once they're in subspace he can no longer help them to get back, and that the Smash Ball will revive the Master Hand and perform this job for them.
Upon entering the portal, Group B falls under attack from the same enemies as Group A. This the second level, in which is a dark purple door with Ridley's face on it. While entering this door s optional, you will trigger a cutscene in which 1 of each of the five species of Shadow Pokemon are centered around a large Ridley trophy. The Pokemon melt into Shadow Bugs and then swarm around the trophy turning into Giant False Ridley.