Hah, in 2.1 dear god.... ive got a SS somewhere of me with 60+ kills.
Wanna win glad mode? Get siren, corrupt flesh, hex, rejuv, and either reinc or death orb.
why? WW! get a second WW item also. WW+juv=win. Hex=no one KS's you, and no one can damage you 1 on 1. Corrupt flesh=only about 1/2 of the people will go for armor rather than damage. -70 armor is a lot, mmkay. reinc? well, reinc, juv, ww!
This is the most overpowered build you can have.. ever!
As a single skill, I would say dread ritual though. Low CD, you can use it every round.. usually... Why? ever see 4 melees going at it, and you cast this on them? BAM, 4 kills. Tidal rush I have also seen get 4-5 kills in a single cast before.
MS is nothing... Hex them before they turn it on, hit their 10 armor with a -70, and they will literally die in 2 hits. IF they start with MS on, you let everyone else burn it down.. then hex and kill.
in 3.0 the siren build doesnt work as good, cuz no innate WW. you can item WW though. even skill WW if you want the extra nuke, but it will hurt later in the game.