One of the plentiful native Stem Ram tribes that ventured further into the Fungal Wastes during the Era of Tribal Peace, the Kalstein tribe, had recently thrived by raiding Stemrail cargo and exchanging it to Under the Tower associates for food, water, and clothes.
They were merely one of many native tribes that preyed on Stemrails until their chief's daughter, Clara Kalstein, grew estranged and violent in XX812. Clara was denied from joining any further raid parties after stabbing Stem City enforcer Fencien Armeldia III during one heist.
Months later, a spiteful Clara blew up a particularly important Stemrail that the tribe was attempting to raid in order to pay off her bounty. This incident caused the once-sediment tribe to become nomadic as Stem Tower placed a public bounty on the "Red Rabbit's" head.
In XX814, the Kalstein Tribe descended on a job that their Under the Tower associate suggested would be able to pay off Clara's bounty and let the tribe live in peace again. Stem Tower's Operation CHAINEDSLIME commenced, with Imine Green slaughtering every single Kalstein tribe member besides Clara.
Running into the Fungal Plains, Clara became the last Kalstein.