Originally Posted by
Fendred
Lets say they have the next raid in some kind of frigid northlands. As a result, players need to gather sets of gear that provide protection against ice damage to survive the environment and its denizens. That is what horizontal progression is. Instead of raising the item level, the raid set has some kind of situational stat. There are various reasons why this is useful, such as countering power creep in a game, but the primary reason a lot of people are asking for it is that WoW didn't do so hot after it raised its level cap too many times.