'Sandscript' is the second half of the starting game for the final episode.
The contestants are split into eight groups, according to the colour of ball they picked up in 'Drop in the Ocean': red, yellow, green, blue, purple, pink, white and black. Tani stands on a platform and calls out a Japanese character. He then picks a ball at random from a box. The colour of ball he picks determines which group gets that character.
This is done seven times for seven characters: "se", "me", "ru", "ta", "ke", "shi", and "jou". The team that doesn't get picked out of the box automatically moves onto the next round.
When the whistle blows, each team has to run over to their giant piece of paper and arrange themselves into the shape of their character. They need to do this correctly so that the phrase "Semeru Takeshi Jou" ("Attack Takeshi's Castle") can be read from above.
When the time is up, the teams are judged on their formation. The team determined the worst loses, and is out of the game.