Cost: +10%
Low Signature reduces the sound of an attack to that of a loud pop of a champagne cork
B106
"If the GM desires extra detail, he can charge +5% per -2 to rolls to notice the ability, and treat -10 (+25%) as “undetectable.” GURPS Powers 103
GURPS Martial Arts under Flying Fists mentions:
- If the victim has never witnessed this ability, he must make a Sense roll at -4 to know he’s being attacked!