A tank wagon can be upgraded twice in [[Game Modes|Endless game mode]]. If players upgrade this wagon, the next iteration will yield a higher capacity water tank making it so that it doesn't need to be cooled as often, as well as increasing the radius of oxygen around it. | A tank wagon can be upgraded twice in [[Game Modes|Endless game mode]]. If players upgrade this wagon, the next iteration will yield a higher capacity water tank making it so that it doesn't need to be cooled as often, as well as increasing the radius of oxygen around it. |