Well... I noticed some diferences of the numberblocks 11 to 20
11/He doesn't have 3 eyes and 10 of the blocks are white.
12/He doesn't have the thing on the right eye, 10 of his blocks are white, he has rectangle eyes and he doesn't wear a hat.
13/10 of his blocks are white.
14/He use a helmet.
15/She doesn't have 3 hands, she doesn't have 3 eyes, hers eyes are shaped as a step shape and 10 of the blocks are white.
16/10 of her blocks are white.
17/ He has 2 eyes, 10 of his blocks are white and the rest are colorful.
18/His eyes are rectangular shape and 10 0f his blocks are white.
19/10 of his blocks are white.
20/His blocks are light orange, he use a hat, his hands are the same as 19, his eyes are the same as 2's eyes and he use shoes.