Some possible ideas.

Rhonas's Monument Pump and trample on creature.

Drumhunter Free draws.

Lurking Predators Another way to cheat things in.

Defense of the Heart A more threatening way to cheat things in.

Arlinn Kord  ^Flip Gives a way, with the flip, to directly deal damage fairly safely if your attack outlets are blocked.

Doubling Season Since you have a lot of token gen, it might be worth sliding this in. Also instants Arlinn to emblem once transformed.

Thanks BlackWyvern, I like these outside the box ideas. Rhonas's Monument is pretty cool! I really wish it was red creatures though...Still, worth considering. Drumhunter has decent synergy with all the fat dragons, but if I were to add more draw I'd probably throw in a non-conditional spell like Harmonize or something, shrug.

Lurking Predators, Defense of the Heart, Doubling Season...Now you're talking. Obviously great cards and I do have copies kicking around so I might mess around, try subbing those in.

Arlinn Kord  ^Flip! I'd written her off as she's just so off-theme, but both her +1's and emblem are pretty great. Interesting.

Add defense of the heart for another tooth and nail. Add Zealous conscripts to combo with kiki-jiki if you can play either tooth and nail. Insta win

Thanks REDWHITEandBLUE, I appreciate the suggestions. I'm considering finding a slot for Defense of the Heart, but I'm steering clear of the famous Kiki + ZC combo as it's simply not the direction I want for this deck - it's a kitchen table tribal/theme deck so I don't want to start adding off-theme infinite combos.

Forkbeard

I've since updated my own Atarka deck with Harmonize as well as things like Bequeathal and Pattern of Rebirth. They work really well if you can slap them on something like Burnished Hart then sac it for two lands, two cards, and a fatty. Also Zendikar Resurgent is another possible source of card draw and directly replaces Mana Reflection in my deck. (I have no tap-mana, everything I run is for land ramp.)

Have you considered Riding the Dilu Horse..? Might lead to a OHKO with the right set up.

Hey ZombieCat - that card looks awesome, I've never seen it before! Even though it's a perfect fit, I'm not sure I can justify the $90 pricetag (damn you Three Kingdoms). I do want to give this deck a bit of a refresh though, maybe take out the 'go wide' effects in favour of 1 shot combat tricks like this.

I prefer Blazing Shoal over Surge of Strength, being able to cast it for free on a hasty Atarka is a big advantage

I like it! Will definitely consider adding, thanks VincentVonVeltschmerz.

Mirrorwing Dragon! Copy your pump spells for all the creatures you control. And if anyone tries to remove it their stuff gets killed too. Nice deck!

Have you considered Soul Foundry and Mimic Vat. The vat is especially good for use as a secondary Feldon of the Third Path and Foundry can work especially well for copying creatures you want more of.

Not a bad idea DoubleSolid, I might try Mirrorwing Dragon out and see how it plays.

Very interesting suggestions dbpunk, thanks!

This deck looks amazing! I just have one question though. Why is Atarka, World Render your commander instead of Dragonlord Atarka?

Thanks QuickNoped! Simply put, World Render is more explosive than Dragonlord. Shame because I love the fact that she's an actual Elder Dragon.

Forkbeard Ok, that makes sense, but wouldn't the 5 damages from Dragonlord every time she comes in be more useful? Basically what I am asking, is will the deck work with Dragonlord as Commander?

Is the 5 dmg useful? Absolutely. Will it win you games? Probably not. AWR is a win-con on her own - with no shortage of haste enabling & combat tricks, it's easy to 1-shot kill with WR straight out of the CZ.

Dragonlord Atarka is a very cool creature and I love the EDH general flavour, but she's definitely the weaker of the 2 IMO.

Forkbeard You sound like you know what you're talking about. Would you mind taking a look at a deck I built and give me some recommendations?

Been a while since I looked at this deck. Happy to see you are keeping it up to date!

Some cards from the new commander decks you should consider are:

Traverse the Outlands - Works well with high power dragons. Territorial Hellkite - has its downside but its power and its casting cost make it worth trying I think. Mirror of the Forebears is almost like having another Kiki-Jiki in your deck. And lastly Herald’s Horn is a cheap way to get extra cards in hand, which gruul can always use.

Thanks LittleBlueHero, I really like both of those C17 artifacts and will try to make room for them in here. I'm not 100% sold on the ramp spell yet but I might pick it up to see how it plays.

QuickNoped - I'll take a look!

As for Territorial Hellkite, he's not strong enough to make the cut. Disappointing as I was hoping for a new dragon from the C17 deck to slot in here.

Love the deck didn't read all comments or revisions, but what about Twinflame.

Twinflame is interesting and certainly fits the theme of the deck. Gonna mull that one over, thanks flyingfox!

I have my own Atarka build as well and I filled it with a ton of ramp to reach the magical 6-7 mana point. With your high mana curve, I'm wondering do you ever have issues with the current build?

Once in a while I get mana hosed but it's pretty rare. I have enough land + ramp in here that the high curve doesn't pose too many problems.