how to make shaman DoT stronger?Follow

ok i'm a lvl 50 Cave Shaman been so for a long **** time no complaints except for the masses of albs and hibs i've wreaked havok on...
i'm a cave shaman because it suits my style of combat best i can use ichor and freeze whole groups then disease them and dot the whole fricken group so not only are they slowed down but their casters cant pull off spells except instas against me and by time they notice me i'm already haulin **** if i'm solo or my group is all over them like a poor barbie at a GI JOE festival...

on keep defense no siege weapons can compare to when i have a screen of 15+ people being hit for 150-250 damage a tick and i hope nobody wunders why the walls of keeps usually stay clean on raids if you have cave shamans it's cause they know if they poke their lil heads up them and everyone around them just got dotted and are now in a world of **** if they dont get cured fast enough... cause they are going to probably be half life if not dead by time that door crashes down..

i am a cave shaman and i have one of midgards most lethal weapons at my disposal it's called the ability to make panic and disorder... a well organized group is pritty useless when their healers are being hit everytime they try to cast and their tanks are being ripped appart and arent moving as fast as their enemies... it's like fish in a barrel if you have an experienced cave shaman...

NOW!!!!!!!! ON TO THE TOPIC AT HAND!!!!
my aoe dot being my primary attack i'm looking for more ways to increase the damage i do i have WA2 almost 3 and i'm going for WA5 what else can i do to increase the damage of my DOT aside from also getting % to spells last longer items....