Azumana, the Aaracokra Wind Warrior

Deceased for many years, Azumana is a great aaracokra warrior who saved his people from sure destruction from an influx of aberrations. 
As such, they returned and quickly buried him in a traditional aaracokra burial that included burying him with one of the creatures he had seemingly killed. Along with this, he was buried with plenty of decorations and offerings from the aaracokra's that were able to flee from the material plane. 
However, over the years, the aberration that a small cult of arracokra priests also burried in a secret room, eventually made its way to the body and gave it new life, causing it to become angry and lash out at anything that entered the temple.