Assassin's Creed: Revelations wants you to Unlock the Animus

Solve a couple of puzzles and you and a friend could be off to visit Istanbul, the modern-day city once known as Constantinople and the setting for Assassin's Creed: Revelations.

Ubisoft has launched a competition to promote the launch of the game on PlayStation 3 and Xbox 360 next month, with flights, four night accomodation and £500 spending money in Istanbul for the grand prize winner and a friend.

On a stand-alone site called Unlock The Animus, players will be asked to solve a variety of puzzles building up to a final brain teaser on November 8.

The first of five "strands", available now, asks players to watch a video and then select from a list of words, identifying 12 elements seen in the video and arranging them in the correct sequence.

You only get five attempts - with the video becoming more and more difficult to understand on each attempt - before you'll be locked out and have to try again somewhere else.

You'll need to sync up your Facebook details or create a log in to be elegible to win, and complete each puzzle in the week of its posting. The second phase of the competition will unlock on October 11.