Hmmm I suppose It depends what आप are doing it for... Are making a symbol for some sort of book are a motif in an artwork?
Perhaps आप should put that into consideration before आप make any decisions. Also look up symbolism that would in fact represent murder या extermination. An example might be blood या the colour red. Find फिल्में या पुस्तकें that affiliate with that genre and try and write things down. If things get desperate आप could even maybe appropriate a डिज़ाइन that appeals to आप and just use that.... That's what I would do anyway. I hope that helps friend! ^^