Ganker: (gayn-kur) noun: A person who is too bad at Dark Souls to ever win a fair fight, and decides to use cheap tactics like 3v1ing and TWoP to get a few bull shit wins so he can feel good about himself.
WoW term. Too stupid to enter a battleground, while also being too idiotic to do something constructive or useful with his/her game time/life, so they are often sighted grouping up and attacking lower level players from behind while they fight something else or recover from a fight.