What about adding Overrun it will make sure your dudes can hit for a crap ton to the face

Or Triumph of the Hordes.

Those are both fantastic cards, the question is what to remove to make room. It's a tough decision as I've spent a lot of time honing this deck and if I were to make cuts, I think I'd opt for 1 hit combat tricks (Stonewood Invocation et al) rather than 'go wide' effects.

This probably won't help this deck, but Atarka, World Render combined with Vorosh, the Hunter would make for an AMAZING dragon deck (Vorosh, the Hunter would get the 6 +1/+1 counters, then hit a second time (doublestrike) with the extra 6 damage)

Heh, yeah. Definitely a sick pairing in a Scion of the Ur-Dragon deck.

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.