Pure Shred - Back?... a brief historical outlook.
The League, while it still fell under the rule of the Council, had faced evil and terrible days. Those days of such legendary items as Malady, which allowed the hairy scientist Warwick to eat a dragon at level 5-6, were coming to a head with so many champions that filled hearts with dread as the speed of their attacks rose. Stuns, poisons, and other unseemly abilities were being driven behind the lash of two and a half attacks per second.
While it is unpleasant to think of, there are countless jungle options that are... for the moment... forgotten. There are many champions who, by default, invoke terror mid/late fight with their existing on attack abilities, and as has been proven countless times... any champion can effectively live in the jungle.
When the Supreme Tank Rule started, a few months before Vayne's arrival... they unleashed Vayne, who became a main staple of any team that wished to accomplish much. This being seen, as opposed to doing anything about it, the Council buried Atma's and found the Blade of the Ruined King. This did, rather effectively, end the reign of the King Tanks, and brought a semblance of peace to that time. While items such as Wit's End still existed, even combined with the Blade of the Ruined King, they just were not enough (in and of themselves) to utterly turn a tide. Thus Pure Shred was, finally, dead. Most attempts to revive it failed utterly, while some semblance of this old demon still poked it's head up now and again.
Then came the dark days. Those days where True Damage became popular once more (despite only two champions wielding this, as it was considered then, ridiculous power). Ah! Now comes the evil that once was. Master Yi, Teemo, Irelia, Vayne, Warwick, and the rest began to roam into the jungle once more. A home to some already, and a tentative location for the rest, the drive to Sate their Devourer was simply too strong. A mockery to the failed Council, as the enchanters cackled with glee... the League once again under the domination of Shred... and this time with no Council to attempt to step in.
AKA: WTF Riot?