Éomer of the Riddermark and Breath of Fury on the battlefield.
Breath of Fury attached to any other creature you control.
You control a creature other than the creature Breath of Fury attached that has the greatest power of creatures on the battlefield.
An opponent cannot block creatures you control.
You control at least one Mountain.
Steps
Declare Éomer of the Riddermark and the creature with Breath of Fury attached.
Éomer of the Riddermark triggers, creating a 1/1 Human Soldier creature token that is tapped and attacking.
Deal combat damage using the creature that has Breath of Fury attached.
Breath of Fury triggers, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to the Human Soldier token, then causing you to untap all creatures you control and to get an additional combat phase after this one.