The Barbarian Slinger can be encountered three provinces of the Early Middle Ages Bonus Questline: Galgenschlucht, Todespass and Steilsturz. It has the ability Last Stand, which gains attack and defense bonus for every unit with last stand that is killed. When these units with last stand ability are killed, every units will be stronger. It also gains bonus on rocks and has unit bonus vs heavy units, but is still vulnerable to fast units. In a battle it looks like a Slinger.
Currently, the player can obtain the Barbarian Slinger only, if he is in possession of an Early Middle Age Timeless Dojo Lvl 5.