I was playing Ascension as Hecarim, and I bought Frozen Heart. Cooldown shows as 30%. If I buy another item that would give me an extra 10% cooldown, the total cooldown stays 30%. If after Frozen Heart I buy Null-Magic Mantle, cooldown seems to be changed to 20% again.
Rosaline1 votesDid you purchase Glacial Shroud before you purchased the full Frozen Heart? There are certain time periods where if you buy a CDR component of an item before the final product, it'll bug and show that you have more CDR than you actually do (the component + final product's CDR added together) but generally goes away after a little while.
DarkBlue871 votesYes, initially it showed 10% CDR, and after the full Frozen Heart 30%. I've noticed that now it takes less time for CDR to go back to 20%.