A 5/5 Human Knight with vigilance and menace for six mana, whenever an equipped creature under your control attacks, you can draw a card for the low cost of losing one life, potentially allowing several additional cards to be drawn in a single turn
This makes Nether Traitor extremely easy to recur, especially in the sort of deck that would want to run it
Milling is also a key part of Jace's theme, to reflect his ability as a telepath to make people forget things: the Living Guildpact, Telepath Unbound, and The Mind Sculptor can all do it very efficiently
She can sacrifice creatures, trigger lifegain, add counters, AND draw cards all for a modest three-mana investment
Yes, Elvish Champion is an elf, which has been updated on all versions from Ninth Edition forward, and appears in the Oracle Text of all versions
Probably not, especially considering they werent worth as much in 2014