10-Man Smash is a Multi-Man Smash (formerly Multi-Man Melee) mode present in Super Smash Flash and Super Smash Flash 2 which originates from the Super Smash Bros. series. It challenges the player to defeat ten opponents without falling from the stage, self-destructing, or being KO'd.
In Super Smash Flash
This mode was originally called 10-Man Melee as it was called in Super Smash Bros. Melee. As with other Multi-Man Melee modes, 10-Man Melee is always played on Battlefield and the opponents are always the Fighting Silhouette Team. It is the shortest of all Multi-Man modes, usually taking just seconds to complete.
Though opponents are light and more prone to being KO'd, SSF's physics make them a bit harder to launch them off the stage with a single attack other than an up attack or a projectile. Additionally, some opponents have access to different moves that allow them to recover with ease and shoot projectiles, which considerably increases the challenge.
In Super Smash Flash 2
This mode is now known under its current name of 10-Man Smash, as it was called in Super Smash Bros. for Nintendo 3DS and Wii U. Much like its predecessor, battles always take place on Battlefield against the Fighting Silhouette Team, who are still light and more prone being KO'd. SSF2 features improved physics, which eases the game mode a lot as the Silhouettes now have a limited moveset, which now prevents them from using special moves, hindering their recoveries.