They beat him
Over the head.
They insulted him.”
καὶ πάλιν ἀπέστειλεν πρὸς αὐτοὺς ἄλλον δοῦλον· κἀκεῖνον ἐκεφαλίωσαν καὶ ἠτίμασαν.
This beating of the second slave can be found in Matthew, chapter 21:36, and Luke, chapter 20:11, but there were multiple slaves in Matthew. Mark said that this landowner again sent another slave to them (καὶ πάλιν ἀπέστειλεν πρὸς αὐτοὺς ἄλλον δοῦλον) in another attempt to get his share of the crop. This time, they beat or struck this 2nd slave over the head (κἀκεῖνον ἐκεφαλίωσαν) and insulted or shamed him (καὶ ἠτίμασαν). These wicked tenants did the same thing to him that they had done to the first slave. There definitely was a pattern developing here.