Sarkhan is an exceptionally powerful card, his lack of pro white and Monstrous ability a small price to pay for his incredible versatility and resilience compared to Stormbreath Dragon. His best friend is, strangely enough, Ajani Steadfast. Lifelink of Sarkhans hasty body is a powerful, game-swinging effect, and the ability of Ajani to either give his dragon form +1/+1 counters or his walker form Loyalty is also impressive.
Running two planeswalkers makes it tempting to run more and go Super Friends, especially with Ajani. Chandra is the 2-of, as her +1 gives us some reach and helps ensure Sarkhan wont be chumpblocked while her 0 ability is a desperately needed source of card draw. Sorin can be considered Ajani #5 as a source of lifelink for Sarkhan, but his ability to generate vampire tokens is a powerful effect and a great plan B, especially alongside Ajani. Finally, Elspeth is simply too powerful a finisher not to run.
Rather than add an extra copy of a current walker or another random 1-of, a lone Chail Veil gives the option to double up on walker activations, which can be absolutely backbreaking here. The rest of the deck is a typical removal suite, albeit one featuring some new Mardu tools like Crackling Doom (a key answer to what I think is an oncoming storm of Monstrous Fleecemane Lions and opposing Sarkhans) and Utter End.
This deck is holding out hope that Mardu Charm is powerful and relevant to its interests or that there is an unconditional kill spell at 1W or 1B or that there is a repeatable card draw effect at 3 or 4 CMC somewhere in Tarkir, so it is very much a work in progress!
