NonCredibleDefense

Explanation: During the Winter War in 1939-1940, the Soviet Union performed an unprovoked invasion of Finland. During the war, one of the lines given by the Soviet official Vyacheslav Molotov was that Soviet planes were dropping aid packages of food, not bombs. This blatant lie was taken by the Finns with dark humor - the Finns said, then, that their improvised incendiary weapons were just 'A drink, to go with the food!'

For this reason, such incendiaries became known as 'Molotov Cocktails', a name they retain to this day.

You need to leave at least fourth or a third of a bottle empty or it won't work. Also you can use acetone to melt polystyrene for added fun (won't be affected by water as much).