I had a ton of fun with this one! I decided to create a mock poster for a Blizzard Entertainment convention of sorts. On the left is the main Pandaren character from World of Warcraft, in the middle is Tyrael the Archangel of Justice from Diablo 3, and on the right is the Protoss Dark Templar Zeratul from Starcraft 2.
I used Adobe Illustrator to create the entire thing, point by point. It was a lot of work, but worth it, in my opinion:
The poster below is the finished product. I chose the colours used in each game section to both represent the characters and to collectively create a colour scheme that would make the Blizzard logo pop out more:
Below is an example of what it would look like as a backlit bus station ad: