Ok i think you never played necro!
ftw hits every 2 seconds and only crit for 700 in t4 gear
and as a crit it activates Lotus overdose wich means you never get the complete damage.
Next thing again you're talkin about icestrike and chill crit numbers like you get that all the time
And you need to use pestilential blast to detonate with chill but there's a high chance that One of these 2 spells gets resisted by lo!
Regards