Classic Mode is a game mode in Smash Bros. Lawl Endgame that allows characters to compete in a tournament similar to in Mortal Kombat or Street Fighter Alpha. However, unlike Classic Mode in the Super Smash Bros. series, this Classic Mode consists of 8 normal battles, 2 rival battles, an optional Bonus Stage, and a Final Boss.
- BRUH (after defeating a Low Rank opponent)
- GET REKT (after defeating the 1st rival)
- U WOT M8 (after failing the Bonus Stage)
- GET NOSCOPED (after defeating a Top Rank opponent)
- OH BABY A TRIPLE (after defeating the 2nd rival)
Like in most other fighting games, characters have rivals they must face in Classic Mode. Each character has two rivals that are fought on the 5th and 10th battles, respectively. Before a rival battle, the two characters exchange dialogue revealing the reason they are fighting. On the final rival battle, the stage is always Final Destination.
Rivals also separate a Classic Mode run into two parts, indicated by the change in fanfare. These parts are Classic Low and Classic Top, as certain characters are placed in one of those ranks (for example: Clarence is Classic Low rank, while Lewis is Classic Top rank).
After defeating the second rival, the player witnesses Segata Sanshiro rising in the background, sending out 0.1% of the power of his fists to fight the opponent. After an epic Master Hand inspired battle, Segata nods, as a cutscene occurs where Chuck grants the player's wish as long as they promise to play Sega Saturn until their fingers broke.