Included are 20,000 Ducats, 12 random paints for your Army, and 3 150% for 24 hours Renown (experience) boosts. Only one per account and supplies are limited, however at time of me posting this there are still few thousand available.
You can get your code at any of these three places:
Gameitems : http://www.gameitems.com/get-your-dogs-of-war-online-tactician-pack-giveaway-758.html
MMOBomb : http://mmo-play.com/rpg-games/dogs-of-war-online/giveaways/dogs-of-war-online-tactician-pack-giveaway
MMO-Play : http://www.mmobomb.com/giveaway/dogs-of-war-tactician-pack-giveaway
