This is debatable, although many people would consider the first arrow into Antinous' throat (the first suitor killed) the first act.
He kills them when they plan to kill Telemecaus and marry his wife.
The Cicone attack on Odysseus and his men was an act of self-defense and revenge. Odysseus and his men killed some of the Cicone and killed some of the sheep and cattle that belonged to them.
Odysseus taunted the blinded Polyphemus in an act of hubris, telling Polyphemus that it was Odysseus who had blinded him.
In the Odyssey, while leaving Polyphemos' cave in Bk 9, Odysseus taunts the blinded Polyphemos until the Cyclops responds by heaving massive boulders. This action of Odysseus' nearly cost him the life of himself and the crew. Once again. this is another unnecessary risk that Odysseus takes, not to mention the fact that he drew the revenge of Poseidon for his son on himself. The extra time that it takes Odysseus on his homeward-bound journey from Troy is a direct result of this prideful act.
he helped odysseus
He kills them when they plan to kill Telemecaus and marry his wife.
Some were afraid that Odysseus might string the bow. Antinous accuses Odysseus of being drunk and having had too much wine. Eventually Telemachus dissipates their protests by threatening to throw stones at Eumaeus if he does not bring the bow to Odysseus; this causes the suitors to laugh heartily.
The suitors act more inappropriate in "The Odyssey" because they believe Odysseus is dead and they see Penelope as fair game as she is resisting remarriage. They take advantage of Odysseus' absence to openly pursue Penelope and indulge in excess and debauchery in his home.
The Cicone attack on Odysseus and his men was an act of self-defense and revenge. Odysseus and his men killed some of the Cicone and killed some of the sheep and cattle that belonged to them.
Polyphemus reveals that his wounded eye was caused by Odysseus and his men when they pierced it with a sharpened wooden stake. This act led Polyphemus to seek revenge on Odysseus and his crew.
In the end of the Odyssey, the cyclops Polyphemus is blinded by Odysseus and his men before they escape from his cave. As a result of this act, Polyphemus calls upon his father Poseidon to seek revenge on Odysseus, leading to further challenges in Odysseus' journey back home.
Its either just "revenge" or "retributions".
The three major plot strands of the Odyssey are Odysseus's journey home from the Trojan War, Telemachus's journey to find news of his father, and Penelope's struggle to ward off suitors and remain faithful to her missing husband.
Odysseus makes the mistake of blinding Polyphemus, the Cyclops, without considering the consequences. This act leads to Poseidon's vengeful wrath, which results in numerous obstacles and delays on Odysseus' voyage back home to Ithaca.
Telemachus proves he can think and act like his father by supporting his father in the battle against the suitors. Also by helping him fight and slay the suitors until they were all dead.
Odysseus taunted the blinded Polyphemus in an act of hubris, telling Polyphemus that it was Odysseus who had blinded him.
In the Odyssey, while leaving Polyphemos' cave in Bk 9, Odysseus taunts the blinded Polyphemos until the Cyclops responds by heaving massive boulders. This action of Odysseus' nearly cost him the life of himself and the crew. Once again. this is another unnecessary risk that Odysseus takes, not to mention the fact that he drew the revenge of Poseidon for his son on himself. The extra time that it takes Odysseus on his homeward-bound journey from Troy is a direct result of this prideful act.