Avestico

The Avestan alphabet is a written-right-to-left system developed from during Iran's Sassanid era (AD 226–651) to record the Avestan language. Avestan was capable of expressing the variety of vowels, however it wasn't quite a useful option.

The oldest manuscript dates back to the XIII-XIV centuries.

As a side effect of its development, the script was also used for Zoroastrianism — an Iranian oldest religion about good and evil. So the method of writing Middle Persian was used primarily for the Zend commentaries on the texts of the Avesta. In the texts of Zoroastrian tradition, the alphabet is referred to as din dabireh or din dabiri, Middle Persian for the religion's script.