I don't know if they changed anything, but Covenant of Champions (basically the first covenant you run across 15 mins in) does not have a great description.
It turns the game into hard mode and does stuff like buff enemy health, resistances, dmg done, etc.
I suggest not joining it.
http://28.media.tumblr.com/tumblr_lcb35gGx0t1qailr4o1_500.gif
http://www.megavideo.com/?v=57N0YAEJ