basically just how much of ap you need to do the same damage as you would with 15% cdr? given for example that you use your skills at least twice after the cooldown goes off. or using different words: what would you rather get? 15 cdr or 50 ap? 100 ap? 150 ap?
12tales4 votesYeah. DPS for mages is essentially a function of Level, CDR and AP, with the exact formula differing for each individual champion. It's pretty easy to quantify exactly what you're getting out of an increase in any of those variables.
Whether or not a given purchase is ideal depends on the champ and your build thus far.
Critkeeper1 votes40% cdr allows for 1/0.6 = 1.66 times the damage output if you spam spells like karthus Q.
In order to get the same 66% damage increase with ability power and if you have 0 ability power, then at max rank you would have to have 264 ability power. If you already have 400 ability power, then the number increases from 264 to 528 (beyond the 400 you already have, for a total of 928) because the 66% damage increase doesn't care if your damage comes from base or from scaling.
so basically, cdr is better for sustained damage on champions that rely on spamming their spells over and over. 40% cdr is hard to acquire through items, but certainly not as hard as 264 or 528 ap.
scaling cdr blues and quints provides 30% cdr at level 18. Abuse it. They are broken as fuck.
SnowFall1 votesI started this thread because recently I'm beginning to be a fan of 9 glyphs lvl18 that give 15% CDR, 20% with 5% CDR from Offense masteries. I used to have ap in glyphs but I think that after buffs CDR glyphs, especially lvl18 ones are strong indeed
SnowFall1 votesSadly there are no items to fill 5% gap if you have 35%