Guerilla Games' Eric Boltjes writes on the Euro PlayStation Blog that they are getting ready for Killzone's 5th birthday with a number things going on over the next few days:

* Looking back at Killzone 1

Later this week on, Seb "Motherh" Downie and I are going to play through the first Killzone game for you. We'll be commenting on our favourite sections and wallowing in beer-induced nostalgia.

* DLC download code giveaway

Haven't checked out the Killzone 2 DLC map packs yet? You're in luck, because Guerrilla is having a DLC download code giveaway. Keep a close eye on this week for full details!

* Killzone 2 retro tournament

This weekend (November 27-30) Guerrilla will host a Killzone 2 retro tournament, using only the Beach Head and Southern Hills maps from the second DLC pack. And there's more to be gained than valor alone, because...

* Double XP Weekend returns

...the tournament will take place during a Double XP Weekend! Just like last time, any game created in the weekend of November 27-30 will yield extra XP to help you boost your ranking.

* Killzone 1 and 2 side-by-side

Finally, editor Victor Zuylen will compare various features of Killzone 2 with its predecessor next week, illustrating exactly how far we've come since the first Killzone game was released.