Not to be confused with Suikoden V's rune of the same name.
The Beast Rune is a True Rune representing animalistic rage and passion.
This rune is officially said to have been given to the Blight family by the High Priest Sasarai. However, the truth is that the Beast Rune refused to be contained within Harmonia and took residence in L'Renouille according to its own will. Harmonia hid this fact by claiming that it was a gift, and used it as a political tool.
Since then, the Beast Rune lay dormant within L'Renouille until Luca Blight took interest in its power. According to Luc, The 'Beast Rune' can only be awakened with a blood sacrifice. After the Beast Rune was realized as a weapon of war, huge quantities of blood was sacrificed to it, awakening various "relatives of the Beast Rune" in the form of golden wolves. These wolves caused confusion to the Allied Forces when they took Muse--the city was filled with golden wolves. During the siege on L'Renouille, the Beast Rune took the form of a Silver Wolf and challenged the Allied Forces to a final bout.
After it was defeated, it is unknown what happened to the Beast Rune.
- The Beast Rune is probably the biggest Rune in the series. It's unknown if a human being would be able to bear it.