Riot say they are still looking into why this exactly is.
Start a Wiki. Dark Harvest Cooldown reduced to 12 seconds from 45.
Corki New Effect: NURF mode punishes mistakes pretty hard which conveniently ends games quickly and prevents them from dragging on too long. April 22nd 2016 URF 3  Everything now deals normal amounts of damage and has normal amounts of health.
Karthus Finishers introduced. Mode Ultra Rapid Fire U.
Karthus Base health reduced to 450 from 528. And the size of the drop-off indicates that it's not just people coming back for URF and then leaving afterwards. Armor growth increased to 4.
There were also some new changes that were not documented. Health growth reduced to 50 from 77. Neville questions Pogba's commitment Claims star has hit form for 'three months' Now that's a golden boot!
Look Before You Leap]. Attack damage growth increased to 4.
The following champions have specific changeS: Disabled Teleport but added the Champion Cannon. Rune balancing: Star Guardian Urgot]. This is a new club membership that lasts for the duration of the event. Contents [ show ].
Riot's post elaborated saying: Health growth increased to 120 from 102. Base health increased to 600 from 565.