Whenever a Dragon you control enters, you may have Sarkhan become a copy of it until end of turn, except its name is Sarkhan, Soul Aflame and it's legendary in addition to its other types.
Ramp into a deck full of Dragons, cast them at a discount, and turn Sarkhan into a copy of each Dragon as it enters for extra ETB triggers and a beefy attacker. You grind board presence with efficient fliers and close games through repeated Dragon damage, copy abuses, and big haymakers like Utvara or Scourge of Valkas.
Cost reduction on every Dragon makes the curve absurdly cheap and lets you double-spell often
Copying powerful Dragon ETBs (and bodies) doubles their impact for free
Evasive, hard-hitting Dragon bodies pressure all opponents in the air
Low mana value (3) means Sarkhan comes down early and starts discounting immediately
Strong tribal support package and payoffs available in Izzet
Heavily commander-dependent; losing Sarkhan removes the discount and copy engine
Vulnerable to board wipes given the deck's high creature count
Dragons are mana-hungry up top despite the discount, so stumbling on ramp hurts
UR lacks reliable creature recursion and struggles against heavy stax or fast combo
The copy is only until end of turn, so it doesn't build permanent board state
Legendary Creature — Human Shaman
less to cast.