The dragon biting itself is a new image instead of the noble and powerful symbol of Kingship and sacredness of Divine Power (Buddhism).
The image of the dragon biting and tearing itself apart is a metaphor expressing the heartbreak of King Ly Nhan Tong when he caused injustice to his loyal teacher - Le Van Thinh because he believed he could turn into a tiger and attact the King.
The painting uses yellow (symbolizing the king) and blue-gray colors to express regret and typical patterns of this dynasty.