Sarkhan, Soul Aflame

He has always been the character who wanted to be a Dragon, not just command them, and this is the version that finally collapses the distance. The copy clause is the whole design: whenever a Dragon lands under your control, this 2/4 Shaman can stop being itself and become a full-fidelity duplicate of whatever just arrived. The retained name is the technical linchpin. Copy a legendary Dragon and Sarkhan would ordinarily be caught by the Legend Rule alongside it; keeping his own name means the copy overwrites everything except his identity, so you get to field a second copy of your best Dragon without sacrificing either. Read the timing, though, because it changes what the card is. The trigger keys off a Dragon entering, and Sarkhan is already on the battlefield when he transforms, so the copy does not re-fire the Dragon's own enters-the-battlefield abilities. What you borrow is the body and the keywords, not the ETB payoff, and only until end of turn. That reframes the card from a value engine into a combat and tempo tool: for one turn you have two of your best evasive threats swinging, then Sarkhan reverts. The cost reduction on Dragon spells does the unglamorous work of getting more Dragons resolved per turn so the copy loop keeps firing. His ceiling is set the moment a Dragon resolves: a small one makes a small Sarkhan, a bomb makes him a bomb. It is a build-around wearing a creature's clothes.