Rather than killing them, an easier way to ruin their existence is scarring them, forever, with [REDACTED PARAGRAPHS: [1+1=3-1(Recreational)]... ...It would stick in their minds, and the minds of everyone who heard the anecdote, and everyone who heard the people who heard the anecdote and passed it on... In addition, you'd probably need to alter yourself to be 'not-Kerrigan' before the original version gets annoyed at a 'not-Kerrigan-but-looks-exactly-like-Kerrigan' doing [REDACTED] and running about causing whatever the 'not-Kerrigan' wants to cause.