What are these Kottabos players holding in their left hand?
It is seen in a lot of similar pictures. It is as if the player refills the kylix from it. Is it a skyphos? Any info on this?
It appears the game involved trying to hit a target with wine lees (fermentation residue). So presumably the bowl in the other hand would hold more wine, with which to refill the drinking cup.
These days the lees is typically filtered out of the wine before the consumer ever sees it, denying us the excitement (not to mention sanitation issues) of this particular game.