A Steam achievement many are seeking to accomplish this holiday season is the "Merry Christmas" achievement in DEFCON. Pretty much all you need to do is nuke Santa Claus who is seen with his signature sleigh and reindeer as a white overlay on the DEFCON map in white. However, the task is kind of hard to do as Santa moves very quickly across the map. So here is what I recommend for all who wish to achieve the death of Claus.
1. Set your computer date to December 24th or wait until that day
2. Make a game with only 1 AI player
3. Set up some silos on the peremiter of your territory and set to Air Defense mode (the default) so that enemy nukes and bombers have less chance at destroying you quickly
4. Set up a few silos near the center of your territory and set them to nuke mode once you get to DEFCON 1
5. You will see Santa flying over different cities and once in Defcon 1 and with some of your silos set to nuke, wait for him to go to one of your enemies cities.
6. Try and guess which city he is going to, and set one nuke ahead of time to that city
7. If there is another town on his flight path, set the other silo to send one there
8. Try and send some bombers as well to the cities if possible as their nukes are harder for the enemy to knock down
9. Hopefully you get lucky and hit Santa
I got this achievement on my first try but it was very difficult. You might have to try a few times or even better get a friend to help you by going against each other and only aiming for Santa, as I believe if either person hits him both get the achievement. Happy Christmas Nuking!