8. The Entente – Deployment of mustard gas in contravention of the Hague Conventions.
The use of poison gas or chemical weapons in war has been prohibited by various treaties since before World War I. An obvious violator might be the GLA faction in Command & Conquer: Generals, whose units spray poisonous green goo everywhere and whose superweapon is an anthrax-loaded ‘Scud Storm’. However, while the GLA are definitely in what the Geneva Conventions would count as an ‘international war’, it’s not clear whether they are signatories to any such agreement, being a bunch of racist terrorist stereotypes who don’t even have any shoes.
We turn instead to The Entente, a World War I themed RTS from Buka Entertainment. The game allows you to research and use mustard gas and other chemical weapons. Even at the time, these weapons were explicitly forbidden by the Hague Convention of 1907 (Hague IV, Article 23), but the cruel, slow deaths they caused – as detailed by Wilfred Owen in his poem ‘Dulce Et Decorum Est’ – were inflicted by all the major powers, making them one of the founding atrocities of the 20th century.
An honourable mention goes to Empires & Allies, the cutesy Facebook war game by Zynga which includes ‘poison gas’ as an upgrade ability. Only its plot set in a fantasy world saved it from top billing in this entry.