Iliad: Ares is hacking through the Greek army on the field of Troy. Athena buffs the Greek hero Diomedes - "guiding his spear" - Diomedes proceeds to pwn Ares, dispelling the God of War and sending him howling back to Olympus.
Iliad: Aphrodite sees a beloved Trojan hero (Aenas?) in trouble, so she manifests to protect him. A Greek hero (Achilles?) stabs her in the hand and she dispels, crying like a girl as she flees back to Olympus. Make love not war, Aphrodite.
It's Diomedes again. (And, yes, Aeneas. Eventual founder of Rome, if you want to believe Virgil. I don't.)
"Now as manslaughtering Ares caught sight of Diomedes the brilliant, he let gigantic Periphas lie in the place where he had first cut him down and taken the life away from him, and made straight against Diomedes, breaker of horses. Now as they in their advance had come close together, Ares lunged first over the yoke and the reins of his horses with the bronze spear, furious to take the life from him. But the goddess grey-eyed Athene in her hand catching the spear pushed it away from the car, so he missed and stabled vainly. After him Diomedes of the great war cry drove forward with the bronze spear; and Pallas Athene, leaning in on it, drove it into the depth of the belly where the war belt girt him. Picking this place she stabbed and driving it deep in the air flesh wrenched the spear out again. Then Ares the brazen bellowed with a sound as great as nine thousand men make, or ten thousand, when they cry as they carry in to the fighting the fury of the war god. And a shivering seized hold alike on Akhaians and Trojans in their feet at the bellowing of battle-insatiate Ares."
Of course, Diomedes needs immortal help against Athene. And Aphrodite is something of a wimp.
[q]Edit: Maybe we have different definitions of 'mortal' - I'd say Elric at the end of Stormbringer was a 30th level PC; Achilles and Diomedes are high Paragon or conceivably early Epic, but definitely all three are still mortal. Hercules would be an Epic PC on the Demigod path, but is dead/ascended by the time of the Iliad.[/q]
By the time you're epic (or attic), you're not entirely mortal.
Cheers!