>>7
It was a block of length 4. On the left side there is a single unit block one unit above the two on either side of it, and a correctly drawn L block one space over. This shows that not only does the artist of >>3 know what a correct L block looks like, and that the unit block below the one of horizontal length 4 a is a block which could be anything, but that whoever was playing fucked up majorly with a length 4 block prior to the one currently in play.