The charge was heralded not by horns, but by the dragon's echoing roar.

Hellkite Courser

Flying
When Hellkite Courser enters the battlefield, you may put a commander you own from the command zone onto the battlefield. It gains haste. Return it to the command zone at the beginning of the next end step.

Flying
When this creature enters, you may put a commander you own from the command zone onto the battlefield. It gains haste. Return it to the command zone at the beginning of the next end step.