Information:  - Left 4 Dead is a cooperative first-person shooter video game with survival horror elements, developed by Valve South and published by Valve Corporation. The game uses Valve's proprietary Source engine, and is available for Microsoft Windows, Xbox 360 and OS X. Development on the game was completed on November 13, 2008, and two versions were released digitally: A downloadable digital version, released on November 17, 2008, and a digital retail disc version, with a release date determined by region. The digital retail disc version was released in North America and Australia on November 18, 2008; and in Europe on November 21, 2008.  - Half-Life 2 (stylized as HLF-LIFE) is a first-person shooter video game developed and published by Valve Corporation. The sequel to 1998's "Half-Life", it was released in November 2004, following a five-year, $40 million development phase, during which a substantial part of the project was leaked and distributed on the Internet. The game was developed alongside Valve's Steam software and the Source engine.  - Minerva ( stylized as MINERVA ) is an episodic series of single - player modifications ( `` mods '' ) for Valve Corporation 's Half - Life 2 . The mod was created by Adam Foster . Installments are released as each is finalized : the three releases for the Metastasis chapter have already been made , with the third installment released on October 1 , 2007 . The plot and settings of Minerva are linked to Someplace Else , Foster 's original map for Half - Life , and to Half - Life 2 itself . The mod was released on Steam on April 30 , 2013 .  - Valve Corporation (commonly referred to as Valve) is an American video game developer and digital distribution company headquartered in Bellevue, Washington. The company is known for the "Half-Life", "Counter-Strike", "Portal", "Day of Defeat", "Team Fortress", and "Left 4 Dead" series, "Dota 2", and its software distribution platform Steam.  - Digital distribution (also called content delivery, online distribution, or electronic software distribution (ESD), among others) is the delivery or distribution of media content such as audio, video, software and video games. The term is generally used to describe distribution over an online delivery medium, such as the Internet, thus bypassing physical distribution methods, such as paper, compact discs, and VHS videocassettes. The term online distribution is typically applied to freestanding products; downloadable add-ons for other products are more commonly known as downloadable content. With the advancement of network bandwidth capabilities, online distribution became prominent in the 21st century.    Given the information above, choose from the list below the object entity that exhibits the relation 'platform' with the subject 'minerva '.  Choices: - internet  - microsoft windows  - steam  - windows  - xbox
microsoft windows

Information:  - The Royal Air Force (RAF) is the United Kingdom's aerial warfare force. Formed towards the end of the First World War on 1 April 1918, it is the oldest independent air force in the world. Following victory over the Central Powers in 1918 the RAF emerged as, at the time, the largest air force in the world. Since its formation, the RAF has taken a significant role in British military history, in particular, playing a large part in the Second World War where it fought its most famous campaign, the Battle of Britain.  - Squadron leader (Sqn Ldr in the RAF and PAF; SQNLDR in the RAAF and RNZAF; formerly sometimes S/L in all services) is a commissioned rank in the Royal Air Force and the air forces of many countries which have historical British influence. It is also sometimes used as the English translation of an equivalent rank in countries which have a non-English air force-specific rank structure.   - Squadron Leader Lord David Douglas - Hamilton ( 8 November 1912 -- 2 August 1944 ) was a Scottish nobleman , pilot , and boxer . He was the youngest son of Lt. Alfred Douglas - Hamilton , 13th Duke of Hamilton RN and his wife Nina , née Poore . Douglas - Hamilton was one of four brothers who made history by simultaneously being at the rank of Squadron Leader or above at the outset of World War II , he himself commanding No. 603 Squadron RAF from 18 December 1941 till 20 July 1942 . Educated at Harrow , and Balliol College , Oxford . Douglas - Hamilton saw active service between 1939 and 1944 , flying Spitfires in Operation Torch over Malta . On return to Britain , he was killed whilst carrying out reconnaissance over the French coast , and crashed in southern England . At the 1934 Empire Games he won the bronze medal in the heavyweight class of the boxing tournament .    Given the information above, choose from the list below the object entity that exhibits the relation 'military branch' with the subject 'lord david douglas-hamilton'.  Choices: - royal air force  - squadron
royal air force