@Kim Budi Spoiler First, I clicked on the Draggable and quickly moved it. Then, I clicked on the block in front of me and brought the Draggable back so he would climb on it. While he was unsteady, I pulled the Draggable away, towards the starting point and he fell. After that, I went to the stairs and repeatedly went back and forth until he was really unsteady, then clicked on the last stair so he would fall on the Win Block.
I liked this level perhaps as a training level. It was not particularly fun. The first part was rather trivial, but the second part took me forever. I think B got tired more than I. Thanks (I think).