I found this to help as well
http://www.ps3trophies.org/forum/assass ... guide.html
Seems we do require the end ones if the guys guide above is accurate.
I never realised that discreet is a high profile kill! Did not even think about it!! Yea the video is definitely one to watch, I know I can nail the Extreme one now that I know the differences of the kills types as listed below!!
1. Discreet
In order to get discreet you need to be in a high profile before killing a target. The top right on HUD will know your consciousness of the way you find your target. And the faster you run the more aware they will know. So you must kill them before you lose your consciousness. This is the highest alertness they will have about you. And pay attention for the level of the alertness.
2. Silent
You must be in a low profile before killing a target. And as same as Discreet, the top right on HUD will know your consciousness of the way you find your target too. When you kill them before you lose your consciousness, and you need to make sure the profile is low. Pay attention for the level of alertness and do not wait too long or it will drop.
3. Incognito
In this part, you need to make sure you have no profile. The top right on the HUD will show you how aware the target is of you. The more you are running around the more aware they will become. So you must not run while the target is near. You can kill them while they have no detection. Killing someone from hay blended, a bench, or even getting the drop on them usually adds the bonus. It's very easy to get the bonus and kill them as well.
4. Acrobatic
You can kill the target from a wall, and jumping from a higher point and executing or hanging. Pay attention for this, the button of execution will show up when the pretty high up.
5. Drop Kill
You can get this on a wall and grab your target while he's on a roof. You must throw him until him dead.
6. Focus
Focus is just a killer where you wait 3 minutes for the circle to fill up around the indicator. It will give you a lot of points if you wait him.
7. Hidden
When you are blended or in hay stack or pile of leaves, Hidden comes along with the hay stack achievement.
8. First Blood
You can get the first kill in the match. And this must be done with at least 3 people.
9. Revenge
Before you kill the target, you must kill someone who had previously killed you.
10. Poacher
When there's 2 people have the same target, you must kill the target in 10 meters while the other one is close.
11. Savior
When you want to do this you must be show your goal in 10 meters.
12. Grounded
When your target is on the ground you can kill it right now. Sometimes they appear with no regularly, so you must be on the alert to them, and kill them in a fast speed when they are on the ground.
13. Mid-Air
You have to hide the gun and pull off the perk. It will be unlocked at level 8, and it usually be used in a private match. When the target goes to the top of the building, you can press the button to lock it on.
14. Poison
You can obtain the poison at level 29. When you are behind the target, you can press the button and kill the target.
15. Intercepted
This part needs 3 people in the game, and 2 of them are targeting the same person. You can kill the target with poison. And at the same time you will get some bonus.