Cooldown reduction effects the rate of which ablilities can be used, as well as summoner spells (ex. Flash, Teleport, Ignite, Etc.) Cooldown reduction like all other stats, can be gained via items, runes, masteries, and through blue buff.
It works at a flat rate, reducing the seconds by your percentage of cooldown reduction.
For example, 10% cooldown reduction would lower a 10 second recharge time by 1 second.
The max cooldown reduction allowed is 40%.
Items[]
(THIS LIST IS NOT COMPLETE)
Image
Name
Price
Description
Ability Potion
250
180s, -10%CD, +25AP
Magna Carta
1125
+30AP, +7MP/5s.
Unique Passive: 10% CD
Book of Elements
1235
+20AP
Unique Passive: Each kill give 2 layers, assist 1 layer, every layer give 5AP, max layers give 15% CD, death loss 1/3 layers.
Dead sea Scrolls
2330
+75AP, +20MP/5s
Unique Passive: 20% CD
Unique Active: Enemy hero get HP/MP regen reduced by 50% for 8s, cooldown 20s.
Glorious Fairy
2600
+80AP
Active: Deal 25% + ( 4% every 100 AP) enemy's current hp as magic damage. Minimum 200 damage, cooldown 60s
Passive: 15% CD
Heart of Fire
3025
+700MP, +10MP/5s, 10%CD
Active: Set fire anywhere on map, after 1.7 sec erupt, deal in 200 AOE 5% of target's max hp.