This Primer is for the development of a competitive Prime Speaker Bant deck. I will attempt to update the Primer as much as possible, and give feedback on posts. Below I will be listing possible card choices, and decklists, including your own decklists if you so choose. Feel free to post your own decks, results, and strategies below.
Loxodon Smiter: Solid uncounterable threat, and great to topdeck late game.
Centaur Healer: Great for the aggro match post side, and a sizable body that can play Defense until you stabilize.
Rhox Faithmender: Double life allows you to outrace almost any aggro deck, but I believe that with 8 sources of EtB lifegain you don't need it
Arbor Elf: The usual mana dork for some lists, I personally don't believe they are needed while the pilgrim is in standard still.
Avacyn's Pilgrim: My go-to choice for mana dorks. Ramps without having to have a ravnica shock and can pseudo mana-fix.
Thragtusk: What's more to say about Mr. Thrag, he's made waves in standard since he was first printed and will be played up until the day he rotates.
Wolfir Silverheart: This guy can make zegana nutty, but until the meta shifts from blitz aggro to a more midrange based meta I'd rather have the Thragtusk as my five-drop.
Restoration Angel: Much of the same reasons above, saves your mana dork from dying in a chump block and allows for the mini-Thrag combo that generates a large amount of card advantage.
Angel of Serenity: A great curve-topper with immediate board impact that can consistently be cast on turns 5 and 6 thanks to our ramp.
Prime Speaker Zegana: The namesake for the deck, comes down with a sizable body and generates enormous amounts of card advantage.
Master Biomancer: Great "value" creature in the midrange matchups, allowing you to severely outclass even the largest threats, and if left unanswered can make bodies big enough to favorably block even craterhoof or Garruk wurms.
Garruk, Primal Hunter: The fourth and fifth Zeganas to begin with, otherwise allows you to present an alternate win condition if you are able to ult him, also helps put the breaks on aggro game 1, and has synergy with Biomancer if you curve out right, making 5/5 beasts is nothing to joke about. Overall the only planeswalker I'd ever consider including
Garruk Relentless: Helps to repopulate the board after a wipe and lets you tutor for threats late game. Don't know how I feel about him yet, he seems a little underwhelming when compared to his big brother, but the G instead of GGG makes him very appealing.
Gideon, Champion of Justice: Can be a suitable planeswalker if your meta is full of aggro, but I think he's better reserved for post-rotation when we need a new 4-drop.
Farseek: Best color fixing ramp in the format, what else is there to say.
Azorius Charm: Let's you gain a tempo boost versus aggro, draw a card late in the game, and is the second half of our sphinx's revelations (lifelink is still a viable mode of this card).
Selesnya Charm: Gives us a mainboard answer to cards like obzedat, and olivia; the trample boost also let's us roll over token decks that are stalling on the ground.
Oblivion ring: Catch-all removal for problem cards like falkenrath aristocrat, boros reckoner, and other problem permanents such as enchantments and the like. Also can target detention sphere which makes it a plus over it's azorius cousin in my opinon.
Detention Sphere: See oblivion ring above, but with the possible outcome of two-for-one trades on your opponent.
Cyclonic Rift: Definitely a sideboard card but has several great applications in board stalls
Syncopate: A great card versus reanimator and other midrange decks where you're looking to counter their haymakers and protect your own