Unfortunately, this is just a cuter version of the original SanGuoSha portait. There does not seem to be any hidden meaning.
Who is he:
Supposedly one of the top 5 generals of the Kingdom of Cao Wei 曹魏, Zhang Liao did not initially intend to follow under Cao Cao 曹操. In fact, Zhang Liao offered his neck for Cao Cao for beheading rather than choose to surrender. While Zhang Liao was serving Lu Bu 吕布, word had already went around of Zhang Liao's combat ability and his righteous character. Guan Yu 关羽 once asked him why he was serving for a man such as Lu Bu and Zhang Liao could only look down in shame. The two later became fast friends, though circumstances dictate they had to be enemies. Zhang Liao achieved renown under Cao Cao as a steadfast and competent general. His title of "General of the Front" was given to him by Cao Pi 曹丕 after Cao Pi succeeded Cao Cao.
Character ability: "Sudden Strike 突击 (tū jī)"
In the drawing phase, Zhang Liao can choose to forgo drawing cards from the deck and, instead, draw 1 on-hand card from other players. Maximum 2 players (2 cards nett intake), minimum 1 player (1 card nett intake).
Note that Zhang Liao cannot mix "Sudden Raid" with drawing from the deck (ie: he cannot draw one card from the deck and one card from a player).
Ability's relation to story:
This part of the story occurs in the battle of He Fei 合肥之战 where Sun Quan 孙权, ruler of Sun Wu 孙吴, led a massive army to attack He Fei. Zhang Liao was one of 3 Cao Wei generals guarding He Fei, but they only had a combined army of 7000 men, many times less than the enemy. Leading the troops out, Zhang Liao bravely charged into the enemy and his combat prowess scared the balls off his enemy. Sun Quan's troops started deserting, not really knowing how large Zhang Liao's army was. Sun Quan climbed up a hill and saw that Zhang Liao was vastly outnumbered. He ordered his troops to encircle Zhang Liao. Unexpectedly, Zhang Liao suddenly charged out of the encirclement (thus the name "Sudden Strike") with a handful of troops and made straight for Sun Quan. The rest of Zhang Liao's troops cried out to him, "General! Have you abandoned us?!" Hearing this, Zhang Liao turned back and rescued his troops from certain death. Both parties grew weary and tired, thus they broke battle and headed back to camp.
Additional info based on story:
1. Most famous achievement - His cursing and swearing at Cao Cao and his refusal to surrender. This occurred early on in the story where Zhang Liao's leader Lu Bu had been executed by Cao Cao. In contrast to Lu Bu, who pleaded for mercy, Zhang Liao cussed Cao Cao endlessly and refused to surrender. Cao Cao was pissed off enough to bring a sword and wanted to decapitate him personally. Zhang Liao responded by sticking his neck out and welcoming death. Liu Bei 刘备 and Guan Yu 关羽 intervened and pleaded for Zhang Liao to be spared. Impressed by Zhang Liao's righteousness and courage, Cao Cao then put down his sword and personally unbound Zhang Liao. It was thus that Zhang Liao came to respect Cao Cao the same and, thence, began a great leader-servant relationship.
2. Cause of death - Zhang Liao suffered an arrow wound after rescuing Cao Pi from Wu forces. Though they were all eventually rescued by Xu Huang 徐晃, Zhang Liao succumbed to his wound and died soon after.