Final answer:
The king's surprise upon seeing Sissa could be attributed to Sissa's unexpected appearance, wisdom, or the implications of his invention, chess. In the case of Hong Pansa (Gil-Dong), the surprise was due to his supernatural mode of arrival and the modesty of his request for recognition given the grandeur of his entrance.
Step-by-step explanation:
The king was surprised on seeing Sissa, a character often linked with the invention of the game of chess, due to the unexpected nature of Sissa's appearance or request. In some stories, Sissa surprises the king by asking for seemingly modest reward of grains of rice doubling on each square of the chessboard, which cumulatively amounts to a vast, unpayable quantity. In other tales, the surprise comes from Sissa's wisdom, innovation, or the profound insights that the game of chess represents regarding the complexities of life and war.
In the case of Hong Pansa (also known as Gil-Dong), the King was taken aback by his arrival on a stork, which is supernatural and out of the ordinary. The anticipation of meeting a heavenly being turned into astonishment when Hong Pansa revealed his earthly identity and intention to be recognized in his rank. This showcases how the unexpected arrival and unusual circumstances can create a sense of surprise for royalty in historical folklore.