From the preview:
Far in the south of Rokugan sits the Kaiu Wall, a hulking shield that defends the Emerald Empire from the horrors of the Shadowlands. Manning this wall is the stalwart Crab Clan, guardians of the Rokugan who sacrifice everything in the name of duty.
Today, we’re previewing the Crab Clan in Legend of the Five Rings: The Card Game. The Crab Clan act as an impenetrable curtain, excelling when defending their provinces and taking calculated losses to gain major advantages.