The signs and who kills them

Aries: a gemini, possibly in cahoots with a scorpio
Taurus: a scorpio
Gemini: immortal
Cancer: a capricorn
Leo: a capricorn
Virgo: an aquarius
Libra: a capricorn
Scorpio: a libra
Sagittarius: a capricorn
Capricorn: cannot be killed
Aquarius: a virgo
Pisces: an aquarius