Runs away with the game at high speeds
Saryth, the Vipers Fang will give all your tapped attackers deathtouch, which combines quite nicely with Doric giving all your creatures trample: deathtouch means just one point of damage is considered lethal to each blocker, and all the remaining damage including the +2/+2 from Doric tramples through
While Red Card can be powerful, having two will not help you if your opponent is not playing Evolutions
In the right application, this can be a much lower-cost version of Farewell or Austere Command when youre in a pinch
Abzan has two turns to discard it from your hand or they are probably stuck on 2 colored mana all game
Then, add in abuse of either the graveyard or creatures with enters-the-battlefield (ETB) abilities, and you have unveiled a card that plays the harpsichord of casual aficionados everywhere