For most of us the round shape is the common association with the coin. May be someone saw or heard about square shape coins. In fact in there are a lot of different form were used by minting a coins in human history. Nowadays with the modern technologies it's not difficult to mint a coin in a huge variety shapes , as you would like. But to cut the difficult picture inside of the borders of the coin , that was difficult goal.
In 2013 first was minted "Crying wolf" silver gilded coin. Where cut-out silhouette was made inside the borders of the coin. It was immediately recognized by numismatics and received Krause's World Coin News Award. Then was minted four silver gilded coins in the series for four years. The last is "Roaring Deer" in 2017 , on the picture. Not understand wrongly , the silhouette is not a paint or sticker.
Looking through the whole coin series you can find the evolution of the "cut-off " technology from the first coin to the last. Much more small details in the shape we could find. From the wool on the comb on the horse to the branched horns on the deer.