TXB ist an encrypted text format, used for several files in Descent. It is a simple bytewise substitution chiffre, but uses Linux-style Line Feeds (LF instead of CRLF).
- CR (0x0D) is discarded
- LF (0x0A) is unchanged
- Other characters are rotated right by 2, and then XORed with 0xE9
- LF (0x0A) is converted to CRLF (0x0D,0x0A)
- Other characters are XORed with 0xE9, and the rotated left by 2. (alternative: rotated left by 2 and then XOR with 0xA7)