The "world" is suddenly overrun by barbarians who appeared from the South! The literal translation of 南蛮入侵 is "under siege from the southern barbarians". The barbarians don't give two hoots about taking sides, they simply slaughter everyone. Every player needs to use an ATTACK card to fend them off or suffer 1 unit of health damage.
What it does:
Delivers 1 unit of health damage to every player (except the user) unless they use an ATTACK card.
How to use it:
Toss the BARBARIANS card into the discard pile. Grimace sadistically as most players whine. Note that it is recommended for players to use their ATTACK cards consecutively one after another, starting from the player on the user's right. This is also the way the San Guo Sha 三国杀 Online game works when BARBARIANS is used (other players are restricted from using ATTACK card until it's their "turn" to do so).
After the death of Liu Bei 刘备 and Cao Cao 曹操, Cao Pi 曹丕 (Cao Cao's son) induced the barbarian forces in the South to invade Liu Bei's kingdom of Shu Han 蜀汉. The barbarians were led by their leader Meng Huo 孟获. Though Meng Huo was a skilled warrior and leader, he was no match for the strategy and mindgames of Zhu Ge Liang 诸葛亮, who captured him seven times! More astonishing was the fact that Zhu Ge Liang released Meng Huo seven times, knowing that to truly quell the rebellion in the south he needed the southerners to respect and admire the Kingdom of Shu Han. Read more about Meng Huo 孟获 and the Southern Barbarians on Wikipedia!
Incidentally, the southern barbarians were the people who invented the RATTAN ARMOR 藤甲.