Garvus was shouting back, but Orun couldn't hear and now the two were separated.  Orun was glad of his own shield, it let him deflect the hydra's heads as they lunged.  Twice he managed to counter attack with slashes at the creature's faces.  When Orun looked to him, he saw that Garvus was trying to form a defensive position, and Orun started trying to move towards him.  If they could reunite, they'd have a chance.  

Orun stepped left and as a hydra head moved to intercept him, he uppercut it with the rim of his shield and slashed its throat.  It bled copious, dark blood onto the sand, splashing Orun, but allowing him an avenue of retreat to the relative safety of Garvus' shield.  When he arrived at his partner's side, he saw the hydra retreating a step.  On head turned inward and used its jaws to chomp down into the base of the injured neck, severing it.  The two gladiators watched in horror as two new heads began to grow in place of the missing one.  But as it grew, the hydra stayed in a defensive stance, the two healthy heads waving like snakes, warning against further attack.  

"Push forward!" Orun called, pointing to the space between the two heads.  "We need to injure it too badly to recover!"  He had already lost his spear, and he quickly switched his sword and shield so that he held a shield on his right side to oppose Garvus' left held shield.  They would need the double sided protection.  Orun planted his feet and prepared to move forward with Garvus as the creature recovered.