IMPORTANT INFORMATION!: For Those So Mad about the Sneaky Stealth kill. Wait for them to turn around. CROUCH!( For you are invisible in that state) Than Press Space Behind Them. They Turn Around because the hear you walking. That is solved by crouching.
Ekuil, If you go too high it makes you stall and fall to the ground and falling from high heights, along with suicide bombing are exceptions to invincibility.
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