This challenge was solved by and the write up was written by one of my teammates, nguyen
From http://asis-ctf.ir/rules/:
=> converts back from hex ‘476f20676f6f2e676c2f67776a625466’ == Go goo.gl/gwjbTf
It is a short link to http://0bin.asis.io/paste/wYO8nWC1#Fef7-CVtrDG7NIb0e1W77+t2jtMF8GSbVHuo6Ajm5RQ that has content: