Since a prophecy suggested that the Trojan War would not be won without Achilles, Odysseus and several other Achaean leaders went to Skyros to find him.
Odysseus discovered Achilles by offering gifts, adornments and musical instruments as well as weapons, to the king's daughters, and then having his companions imitate the noises of an enemy's attack on the island (most notably, making a blast of a trumpet heard), which prompted Achilles to reveal himself by picking a weapon to fight back, and together they departed for the Trojan War.

The story of the death of Palamedes has many versions.
According to some, Odysseus never forgives Palamedes for unmasking his feigned madness and plays a part in his downfall.
One tradition says Odysseus convinces a Trojan captive to write a letter pretending to be from Palamedes.
A sum of gold is mentioned to have been sent as a reward for Palamedes' treachery.
Odysseus then kills the prisoner and hides the gold in Palamedes' tent.
He ensures that the letter is found and acquired by Agamemnon, and also gives hints directing the Argives to the gold.
This is evidence enough for the Greeks, and they have Palamedes stoned to death.
Other sources say that Odysseus and Diomedes goad Palamedes into descending a well with the prospect of treasure being at the bottom.
When Palamedes reaches the bottom, the two proceed to bury him with stones, killing him.

When Achilles is slain in battle by Paris, it is Odysseus and Telamonian Ajax who  retrieve the fallen warrior's body and armour in the thick of heavy fighting.
During the funeral games for Achilles, Odysseus competes once again with Telamonian Ajax.
Thetis says that the arms of Achilles will go to the bravest of the Greeks, but only these two warriors dare lay claim to that title.
The two Argives became embroiled in a heavy dispute about one another's merits to receive the reward.
The Greeks dither out of fear in deciding a winner, because they did not want to insult one and have him abandon the war effort.
Nestor suggests that they allow the captive Trojans decide the winner.
The accounts of the Odyssey disagree, suggesting that the Greeks themselves hold a secret vote.
In any case, Odysseus is the winner.
Enraged and humiliated, Ajax is driven mad by Athena.
When he returns to his senses, in shame at how he has slaughtered livestock in his madness, Ajax kills himself by the sword that Hector had given him after their duel.

Together with Diomedes, Odysseus fetches Achilles' son, Pyrrhus, to come to the aid of the Achaeans, because an oracle had stated that Troy could not be taken without him.
A great warrior, Pyrrhus is also called Neoptolemus (Greek for "new warrior").
Upon the success of the mission, Odysseus gives Achilles' armour to him.

It is learned that the war can not be won without the poisonous arrows of Heracles, which are owned by the abandoned Philoctetes.
Odysseus and Diomedes (or, according to some accounts, Odysseus and Neoptolemus) leave to retrieve them.
Upon their arrival, Philoctetes (still suffering from the wound) is seen still to be enraged at the Danaans, especially at Odysseus, for abandoning him.
Although his first instinct is to shoot Odysseus, his anger is eventually diffused by Odysseus' persuasive powers and the influence of the gods.
Odysseus returns to the Argive camp with Philoctetes and his arrows.

Perhaps Odysseus' most famous contribution to the Greek war effort is devising the strategem of the Trojan Horse, which allows the Greek army to sneak into Troy under cover of darkness.
It is built by Epeius and filled with Greek warriors, led by Odysseus.
Odysseus and Diomedes steal the Palladium that lay within Troy's walls, for the Greeks were told they could not sack the city without it.
Some late Roman sources indicate that Odysseus schemed to kill his partner on the way back, but Diomedes thwarts this attempt.
Since a prophecy suggested that the Trojan War would not be won without Achilles, Odysseus and several other Achaean leaders went to Skyros to find him. Odysseus discovered Achilles by offering gifts, adornments and musical instruments as well as weapons, to the king's daughters, and then having his companions imitate the noises of an enemy's attack on the island (most notably, making a blast of a trumpet heard), which prompted Achilles to reveal himself by picking a weapon to fight back, and together they departed for the Trojan War.
The story of the death of Palamedes has many versions. According to some, Odysseus never forgives Palamedes for unmasking his feigned madness and plays a part in his downfall. One tradition says Odysseus convinces a Trojan captive to write a letter pretending to be from Palamedes. A sum of gold is mentioned to have been sent as a reward for Palamedes' treachery. Odysseus then kills the prisoner and hides the gold in Palamedes' tent. He ensures that the letter is found and acquired by Agamemnon, and also gives hints directing the Argives to the gold. This is evidence enough for the Greeks, and they have Palamedes stoned to death. Other sources say that Odysseus and Diomedes goad Palamedes into descending a well with the prospect of treasure being at the bottom. When Palamedes reaches the bottom, the two proceed to bury him with stones, killing him.
When Achilles is slain in battle by Paris, it is Odysseus and Telamonian Ajax who  retrieve the fallen warrior's body and armour in the thick of heavy fighting. During the funeral games for Achilles, Odysseus competes once again with Telamonian Ajax. Thetis says that the arms of Achilles will go to the bravest of the Greeks, but only these two warriors dare lay claim to that title. The two Argives became embroiled in a heavy dispute about one another's merits to receive the reward. The Greeks dither out of fear in deciding a winner, because they did not want to insult one and have him abandon the war effort. Nestor suggests that they allow the captive Trojans decide the winner. The accounts of the Odyssey disagree, suggesting that the Greeks themselves hold a secret vote. In any case, Odysseus is the winner. Enraged and humiliated, Ajax is driven mad by Athena. When he returns to his senses, in shame at how he has slaughtered livestock in his madness, Ajax kills himself by the sword that Hector had given him after their duel.
Together with Diomedes, Odysseus fetches Achilles' son, Pyrrhus, to come to the aid of the Achaeans, because an oracle had stated that Troy could not be taken without him. A great warrior, Pyrrhus is also called Neoptolemus (Greek for "new warrior"). Upon the success of the mission, Odysseus gives Achilles' armour to him.
It is learned that the war can not be won without the poisonous arrows of Heracles, which are owned by the abandoned Philoctetes. Odysseus and Diomedes (or, according to some accounts, Odysseus and Neoptolemus) leave to retrieve them. Upon their arrival, Philoctetes (still suffering from the wound) is seen still to be enraged at the Danaans, especially at Odysseus, for abandoning him. Although his first instinct is to shoot Odysseus, his anger is eventually diffused by Odysseus' persuasive powers and the influence of the gods. Odysseus returns to the Argive camp with Philoctetes and his arrows.
Perhaps Odysseus' most famous contribution to the Greek war effort is devising the strategem of the Trojan Horse, which allows the Greek army to sneak into Troy under cover of darkness. It is built by Epeius and filled with Greek warriors, led by Odysseus. Odysseus and Diomedes steal the Palladium that lay within Troy's walls, for the Greeks were told they could not sack the city without it. Some late Roman sources indicate that Odysseus schemed to kill his partner on the way back, but Diomedes thwarts this attempt.
Odysseus