It's not called attunement any more, and it's not a hard requirement now, but attunement is back, in a new guise, and it's called Reputation. Let me come right out up front and tell you I welcome this.
I just finished the questline to earn my Sha-touched gem. It took me 108 raid boss kills to earn the requisite amount of sigils and the chimera of fear required for Wrathion to forge my Crystallized Horror (I could have done in in fewer kills, if I'd known what I was doing). Now he has me on two new quests: Earn 6000VP! and kill horde until I'm revered by him. Why would I do that? And why would I earn reputation with any of the other factions? the short answer is, for their rewards. Great weapons and armour are locked behind these reputation grinds. And why do we want these weapons and armour? Because we're stuck on a particular raid boss. Any edge we can get is worth the grind.
Now we can get into any raid instance without attuning to it. But getting far into the instance is another matter. If you're like me, you'll need to earn the reputation to get the gear. In fact in my case, because I'm raiding with another guild, I need the gear to keep my performance high enough to keep my raid spot!
What does TiDi tell us about EVE? - TiDi is an anti-lag mechanic, increasing the cycle time of modules, therefore decreasing the amount of server queries the player can reasonably start. But ...
1 hour ago