The challenge finished last week and I fell a little behind! But I will still finish it. Hopefully I should be posting twice this evening to catch up.
Firstly day 23 was to start putting the perspective grids into practice by adding figures into them and seeing how different parts of the figure are affected when above and below the horizon line (thinking back to day 22 on how the cylinder's top and bottom curves were affected).
The skill check was to just let loose on a figure drawing with perspective grid.