Just reading the Yuddha Kanda, one can understand why Lord Krishna while describing excellent amongst all, said he is Rama among the weiders of weapon:
पवन: पवतामस्मि राम: शस्त्रभृतामहम् |
झषाणां मकरश्चास्मि स्रोतसामस्मि जाह्नवी || B.G 10 : 31||
Amongst purifiers I am the wind, and amongst wielders of weapons I am Lord Ram. Of water creatures I am the crocodile, and of flowing rivers I am the Ganges.
Sri Rama singlehandedly killed ten thousand chariot warriors, eighteen thousand elephants, fourteen thousand horses and two lacs foot soliders, in span of 3 hours:
Within a matter of three hours, with his arrows looking like tongues of flames, Rama killed an army of demons, capable of changing their form at will, including ten thousands chariots possessing the swiftness of the wind, eighteen thousand strong elephants, fourteen thousand horses with their riders and a full two lacs of demons fighting on foot.
When Rama was fighting, rakshasha could not even see Sri Rama, because of his swiftness in martial arts. So swift was Rama in fighting skill, that rakshhasha were confused and started to kill one another:
Those highly terrific demons dared not approach Rama, having entered their ranks, was scorching them with the flame of his arrows, even as clouds would not approach the scorching sun in the sky.
One Rama appeared to be 1000, when rakshasha saw him because of his swiftness of killing. One moment they see Rama, one moment they get killed, such was their condition:
Those demons for their part saw thousands of Rama's in the battle-field, while at other times, they saw only one Rama in that great battle.
No one in the entire epics has ever fought fiercely like Sri Rama! Such momentum he had, such force he had, that through one arrow he was able to tear 7 sal trees apart:
The golden arrow released by the mighty Rama perforated all the seven sala trees, and even the levelled areas of mountain, and then entered the earth.
He destroyed 14000 rakshashas including Khara and Dushana, single handedly:
There were fourteen thousand rakshasas who were terrible in their valour. A single one on foot slew them with sharp arrows, together with Khara and Dushana, within the space of one-and-a-half muhurtas
Rama and lakshmana together wiped out 1/3rd army of rakhasas on day one completely at night time .
Rama and Lakshmana killed the foremost of the demons, both those who were visible and those who were invisible, with their arrows resembling venomous snakes.
Rama the great warrior, merely within an instant, made the quarters and the intermediate quarters, clear of all the demons, by his arrows resembling flames of fire.
When Indra’s son Jayanta(in crow form) in lust was pecking on Mata Sita,seeing his dear wife in pain Lord Rama threw the grass blade to Jayanta, turning it to Brahmastra.
Shri Rama defeated Ravana during their 1st encounter and spared his life :
In that battle-field, Rama said to that Lord of Demons whose splendour was dimmed, the setting of his diadem river, who resembled a venomous snake robbed of its poison or like a sun its rays extinguished, bereft of lustre.
"You have accomplished a highly terrific great feat and my brave soldiers have succumbed beneath your blows. Now, you are weary and in this condition, I shall not put you under the clutches of Death."
Sri Rama’s arrow made ocean tremble:
The great jerk of water with fishes and alligators of the ocean, together with the resonance of the wind became very much dreadful.
Immediately that great ocean, became shaken by the cluster of huge waves enveloped by a multitude of conches in its rolling waves and a smoke came out
Sri Rama was capable of destroying all worlds together, and was also capable of creating the world in same manner as before:
"The renowned Rama is capable of totally destroying all the worlds together with its five elements, along with its animate and inanimate things and also to create yet again all the worlds in like manner as before."
Lord Hanuman says neither Lord Brahma nor Rudra nor Indra can protect someone from Rama in the battlefield:
Either Brahma the self-existing god with four faces or Rudra with three eyes and the destroyer of Tripura (the city built of gold, silver and iron in the sky, air and earth, by Maya for the demons and burnt by Shiva), or Mahendra the god of atmosphere and sky as also the lord of celestials would not be able to protect the one to be killed by Rama in battle."
So, there in every kanda you will find the reason why Sri Rama is greatest warrior to be ever born.
About defeat, no one can defeat Lord Rama. Sri Rama himself says, only Mahadev is his equal:
Then, the virtuous Rama spoke also to Sugreeva, Vibhishana, Hanuma the monkey, Jambavan, Mainda the foremost of monkeys and even Dvivida, who were in close proximity to him as follows "Such wonderful power of this missile exists either with me or with the three-eyed Rudra the lord of destruction."
Siyavar Ramachandra ki Jaya!