Sandbag (サンドバッグくん, Sando Baggu-kun, Punching Bag) is a character who stars in the Stadium game Home-Run Contest in both Super Smash Bros. Melee and Super Smash Bros. Brawl, and appears as a regular item during matches in Brawl.
Sandbag's most prominent appearance is in the Home Run Contest, a minigame where players are given 10 seconds to rack its damage up and hit it as far as possible using a Home-Run Bat. In this game, Sandbag has a visible damage percentage, and flies farther when hit at higher percentages, much like characters do. When hit off the starting platform, the camera follows Sandbag until it lands and stops moving. According to its Melee trophy description, Sandbag is not hurt by attacks, and 'loves to see players wind up and let loose'.
 In Super Smash Bros. Melee
In Melee, Sandbag is technically defined as a non-playable character, and therefore can be grabbed and thrown by players, and it is programmed not to move. Although Sandbag cannot normally be controlled by human players, it is possible to circumvent this through the use of Action Replay. Doing so allows players to control it and make it move and jump, however, attempting to make it attack causes the game to freeze, and has other problematic effects. Sandbag has no animations, it uses its "idle state" when it moves manually and jumps. Using moveset swap hacks, it is possible to give Sandbag the moves of a playable character. However, attempting this may still cause the game to freeze. As a character, Sandbag is unusual in that it cannot be KOd. This is because the only stage on which it is meant to be found is the Home-Run Stadium.
In both Melee and Brawl, the Sandbag trophy is obtained by completing the Home-Run Contest with every character. Note that characters who may be switched during matches, namely Zelda and Sheik, Samus and ZSS, and the Pokémon Trainer's Pokémon, need not all be used, one each is sufficient.
 In Super Smash Bros. Brawl
In Brawl, Sandbag has become lighter and now slides farther a few hundred feet after landing from a hit. It is also defined as an item, and therefore cannot be grabbed by regular or special grabs. Its programming contains unused subactions for character-based situations, such as the event of being grabbed, which suggests that it the game's developers may have formerly intended that it remain a character. While it cannot be grabbed, Sandbag can be eaten by Kirby and King Dedede's Inhale, and Wario's Chomp, but only during matches. As well as its appearance in the Home-Run Contest, Sandbag may appear as an item during matches. It may release more items when characters hit it. As with "container items", such as Crates and Capsules, the types of items it releases during Multiplayer matches and in Training Mode are determined by the game's item settings, however, it is not classified as a "container item", cannot be carried and cannot explode. In matches, Sandbag takes little horizontal knockback and cannot be KOd by the upper blast line. Sandbag also appears in the Online Practice Stage, where players may attack it while waiting for Wi-Fi matches to start.
Sandbag's cute appearance and comical role in the series has earned it a fanbase. This fanbase was enough to earn Sandbag a position in the bracket for GameFAQs 7th character battle. Sandbag made second place in the first round, but was defeated in the second round.
 Description from the Super Smash Bros. Brawl instruction booklet
Can produce items each time you hit it.
 Melee trophy
 Brawl trophy