William Edward Sing, DCM (3 March 1886 – 19 May 1943), known as Billy Sing, was an Australian soldier of Chinese and English descent who served in the Australian Imperial Force during World War I, best known as a sniper during the Gallipoli Campaign. He took at least 150 confirmed kills during that campaign, and may have had over 200 kills in total. However, contemporary evidence puts his tally at close to 300 kills.

https://en.wikipedia.org/wiki/Billy_Sing