This is the simplest, that is, add up all items, skills, talents, runes to reduce cooling, and calculate them uniformly. The leftmost attack talent in the talent has a cooldown reduction in the first row, which can reach 5% at most. With 15% bright boots, plus some things like Molor's secret book, the Great Grail and Frost Heart, you can reach the upper limit of 40% cooling reduction.

There are only three issues to consider:

First, except for the unlimited firepower mode that is open for several weeks every year, all other modes have the same upper limit of cooling reduction, with a maximum reduction of 40%. In other words, a skill can be played once every ten seconds without any cooling, so it can be played once every six seconds under extreme cooling. In unlimited firepower mode, the cooldown of all skills is reduced to one-fifth of the original, that is, the cooldown is reduced by 80%, and it cannot be further improved.

Second, occasionally there will be some equipment, and their cooling reduction is the only passive, so at most only one such equipment can be produced. However, this situation is very rare. I can't remember whether that piece of equipment is an ancient will or a spiritual wind.

The third is to consider whether it needs to be superimposed to the degree of extreme cold.