Custom text boxes

Bulbapedia also has an article about Custom text boxes.

Custom text in a custom map from TheZZAZZGlitch's creepypasta save file

Using text pointers sourced in RAM, the player can use arbitrary code execution to write and show custom text boxes.

In Generation I

There are many means of displaying custom text boxes in the game, including:

• Text pointer manipulation
• Glitch sign manipulation (the basis of Pikachu off-screen glitch arbitrary code execution)
• Text box ID matching (e.g. Sea Route 21 0x44 text box glitch (English Yellow))
• Custom Pokédex entries

Specific details on how to bring up the text box pointer are detailed in the articles above.

Formatting

This article is incomplete. Please feel free to add any missing information about the subject. It is missing: Other text commands such as the one to print numbers.

Text boxes in the game begin with a special command, detailed as such:

• 00: Normal text. Text characters (found on The Big HEX List) follow. If an 0x00 byte appears in this region, an error code will appear and text following it will not be printed. Some characters are control characters which will automatically print a string, line break, new page, etc.
• 08: Runs code following the 08 byte (can be used for arbitrary code execution)
• F5: Loads a vending machine
• F6: Loads Cable Club reception lady text
• F7: Game Corner Pokémon prize menu. The prizes are determined by the text box's index number, stored at FF8C. Some glitch Game Corner prizes also cause buffer overflows. See PrizeDex for more information.
• F9: Normal PC
• FC: PC for items only
• FD: PC for Pokémon storage only (unused, featuring "Switch on!" text)
• FE: Loads a Poké Mart
• FF: Loads a Pokémon Center

For further information, see the Bulbapedia article.