So, as far as obscure questions go this one takes the cake. But it’s fairly workoutable and fair-fodder for Boiledbeans, so here goes.

What’s so special about the circle?

Cracked by: jayanth , Rogi , Shrey Goyal , finkle , Manish Achuth , , Sumanth Patlolla , rickde , Bharath , Ananth , badideabear , Bipin Banavalikar , Mayukh Bose , KK , raklodramA , Amarendra Kumar , Raghuvansh and piezocake

Answer:
Prince of Persia source code