Hypothermia Gem question

If I'm using Storm Brand which is entirely lightning, but I want to use it in a helm with Hypothermia, how much cold damage do I actually need to make it work?



Could I just use 1 abyss jewel with cold damage, and it'll make my hypothermia gem work with Storm Brand?

Or is there some minimum I have to hit in cold damage?

All ailments are determined by comparing the damage trying to inflict it with the ailment threshold of the target. In case of chill you need to achieve at least 5% otherwise it's discarded. Depending on what you are hitting you'll need a significant amount of damage to accomplish this. POB can tell you how much in detail. The kind of helmet you wanna use is typcially used with 2 of those lightning to cold conversion rings so you should do just that.

Alternatively, use skitterbots.