Sun Quan's ability "Balance of power" becomes literal here as the artist gave him two mugs of beer to balance in his arms!
Who is he:
One of "the Three", Sun Quan is the ruler who ultimately formed the Kingdom of Sun Wu 孙吴. He took over the reigns of ruler from his elder brother, Sun Ce 孙策, at the age of 18 and led the Wu Kingdom till his death at 70 years old. He is the longest serving ruler of the era. Compared to Sun Ce who was known as the "Little Conqueror 小霸王", Sun Quan was not as strong a combat fighter, but he was able to win the hearts and respect of his generals and people. He was surrounded with loyal and capable talents, which he prudently retained. The Kingdoms of Sun Wu and Shu Han 蜀汉 formed an alliance to resist Cao Cao 曹操's attacks. However, Sun Quan's short alliance with Liu Bei 刘备 became a sore point as the wits of Sun Wu were no match for the prescient Zhu Ge Liang 诸葛亮. Regardless, the Kingdom of Sun Wu lasted longer than both Cao Wei 曹魏 and Shu Han. It was the last to be defeated by the Si Ma 司马 family, which marked the end of the Three Kingdoms era and the beginning of the Jin Dynasty 晋朝.
Character ability 1: "Balance of Power 制衡 (zhì héng)"
During the action phase, Sun Quan can discard any number of his cards (both on-hand or equipped) and draw the same number of new cards from the deck. Limited to once per turn.
Character ability 2: [Ruler ability] [Enforced ability] "Rescued 救援 (jiù yuán)"
When Sun Quan is rescued from the brink of death by other Wu characters via the use of PEACH 桃, Sun Quan recovers 1 additional unit of health (from zero health to two units of health).
Ability's relation to story:
"Balance of Power" refers to Sun Quan's decision to ally with Liu Bei so as to counter the immense army of Cao Cao. Before the battle of Red Cliffs 赤壁之战, Cao Cao has already amassed an army far greater than either Shu Han or Sun Wu. With the alliance, both the kingdoms were able to restore the balance of power and prevent a complete runover by Cao Cao. "Rescued" could be referring to Zhou Tai 周泰's rescue of Sun Quan from numerous near-death encounters. Though it is unfair to single-out Zhou Tai for commendation, the story places great emphasis of Zhou Tai's sacrificial (sometimes suicidal) charges to rescue Sun Quan.
Additional info from the story:
1. Most famous achievement - Setting up the Wu Kingdom and having ruled it well from 18 to 70 years old.
2. Cause of death - Sun Quan died of old-age, though it can also be reasonably said to be due to illness. Either way, he was not killed in action. Besides, living till the age of 70 in that era is a feat on its own.