Another event for you to consider staying a little longer in Cologne after Evoke is Respawn - gathering of game developers.
The freshingly new games conference is also happening in AbenteuerhallenKalk (so you will not have problems finding the location) on Monday and Tuesday after Evoke!
It features talks on major game development and marketing issues, such as game design, art direction, coding, sound design and business happening at different spots in the large hall. In addition they will offer a bbq on Monday and a closing party on Tuesday! In total: a great warm up for gamescom!
Tickets are available starting at 59 Euro.