What magical ability does the donkey possess in the painting?

Spewing arrows

Answer: The donkey with magical powers is spewing arrows at Kalaka’s army of kings.

Kalaka is seen on the lower right and his captive sister is depicted towards the top left. The donkey with magical powers is spewing arrows at Kalaka’s army of kings. The evil king presides from inside the circular fort.

Kalakacharyakatha narrates the story of Acharya Kalaka, who is on a mission to rescue his abducted sister (a Jain nun) from an evil king. It recounts various thrilling episodes and adventures of Kalaka, such as him scouring the land to locate his missing sister, demonstrating his magical powers, forging alliances with other kings, and lastly, battling the evil king.