Which retro Nintendo game themes the standard mode in Tetris DS?

The standard mode in Tetris DS is themed around Super Mario Bros.

Unlike the game’s more experimental modes, Standard mode keeps the familiar falling-block format while placing the action in a Mario-styled presentation. Mario and scenes inspired by the classic platform series appear as the player clears lines and advances, with music and visual elements drawing on Nintendo’s 1985 hit.

Tetris DS contains several other Nintendo-themed modes, which is why the answer can be confused. Mission mode uses The Legend of Zelda imagery, Catch mode draws on Metroid, Push mode is associated with Donkey Kong, and Touch mode uses Balloon Fight-inspired presentation. Those are alternate modes, not the theme of the default standard experience.

Tetris DS was developed and published by Nintendo for the Nintendo DS in 2006. Its central appeal was the contrast between traditional Tetris rules and a gallery of recognizable Nintendo characters, sounds, and settings. Standard mode is therefore both the most straightforward mode and the clearest Mario crossover.