The Improved Shadow Blend is a skill exclusive to challenge 13 "Hide and Seek" and is an upgrade of Shadow Blend. With this skill, you will be practically invisible--even while walking, which the original Shadow Blend could not do. The only way to be seen is to attack or be attacked. The ninjas in challenge 8, "Ninja Assault" have this ability as well. However, even though it might be improved, it can still be picked up by an Assassin armed with Full Radar and/or Vital Sight. Strangely, even though AI armed with laser sight can have their laser land on you, they will still not shoot.