A balbal is one of the stone figures raised beside a burial mound on the steppe. Most show a person: a rough silhouette holding a cup, a knife at the belt, a face cut into the stone.
What they are is argued over. One reading makes them the enemies the buried man killed, standing to serve him in the next world; another makes them ancestors, keeping watch over the grave. Some kurgans have a single balbal; others have hundreds in a row.
The game takes its name from them, and the reason is visual: stones with marks carved into them, laid out in a line is already a mahjong board. The Barrow floor builds that view directly — mounds at dusk and rows of figures.