Left 4 Dead
65 Achievements
1,500
50-64h
Xbox 360
Xbox One
Xbox Series
Spinal Tap
Kill an Infected with a single blow from behind.
10
How to unlock the Spinal Tap achievement in Left 4 Dead - Definitive Guide
Krimp
TrueAchievements
TrueAchievements
Make it easy on yourself, pick up a propane tank, get behind any regular infected and melee. You should pick this one up on the first attempt.
Kindredfool
TrueAchievements
TrueAchievements
I'm suprised I didnt get this earlier! I somehow avoided it up until the 600G mark, and if you havent got it here is a little strategy.
No Mercy
Part 1
As soon as you start, turn off your light and run down the stairs. Once you get to the bottom there will be some Infected walking around gormlessly, and the chances are one will be facing away from you. All you do is run up and Melee (LT) them on their upper back, the Infected will just drop in a heap.
Tip: Dont do this slowly, don't crouch and turn off your torch on the way down, just walk quickly down the stairs and proceed as above.
And thats how I did it, It's an easy achievement.
No Mercy
Part 1
As soon as you start, turn off your light and run down the stairs. Once you get to the bottom there will be some Infected walking around gormlessly, and the chances are one will be facing away from you. All you do is run up and Melee (LT) them on their upper back, the Infected will just drop in a heap.
Tip: Dont do this slowly, don't crouch and turn off your torch on the way down, just walk quickly down the stairs and proceed as above.
And thats how I did it, It's an easy achievement.
4 Comments
This method doesn't work, don't waste your time trying to pop the cheevo this way. The zombie will ALWAYS turn around/spot you before you can ever get close enough.
By CruelCahal on 24 Oct 2013 12:19
didnt get it on the stairs but just around the corner - positive vote
By Woodster 86 on 30 Jan 2014 23:05
Pyroman31, Metaphorically, KutleryKing
The Infected can be killed easily from behind by punching them. Just as long as they don’t know you’re there, of course. Start up the No Mercy campaign from the Apartments. It’s easier here because the first Infected you run into, don’t attack right away. Just run up behind one, and press 
to melee them right in the back of the head.
Imadori
stratege.ru
stratege.ru
This guide was translated automatically.
While going through the company, you will come across infected people who are standing and resting their heads against the wall, ala drunk =). So turn off the light and run up to him from behind, press 
aiming for the head area.
aiming for the head area.