Indeed, there is a certain irony in Hamlet's soliloquy of Act IV when he observes,
How all occasions do inform against me,
And spur my dull revenge! (4.4.32-33)
Despite Hamlet's reluctance to act, he, nevertheless, leaves many in his slow wake. A complex character, Hamlet is a mix of tenderness and love, friendship and deadliness. Here are some tragic incidents precipitated by Hamlet upon people to whom he has attachments [the incidents are described after the characters]:
The death of Polonius - When the devious and meddling Polonius decides to listen in on Hamlet's conversation with his mother by hiding behind the arras, Hamlet stabs him, believing that King Claudius is listening. Angered at the meddler, Hamlet decries him,
Thou wretched, rash, intruding fool, farewell!
I took the for thy better. Take thy fortune. (3.4.33-34)
The deaths of Rosencrantz and Guildenstern - These former schoolmates of Hamlet's conspire against him for King Claudius; so, when Hamlet is sent to England, they escort him. But, when their ship is attacked, Hamlet leaves them to die. In Act 3, he has told his mother, "I will trust [them] as I will adders fang’d" (3.2.)
The death of Ophelia - Hamlet's rejection of her, accompanied by his cruel words--"Get thee to a nunnery!" (3.1.119)--and with her depression over her father's death at the hands of Hamlet gives Ophelia more than she can bear. She kills herself in her despair.
The death of Claudius - After Hamlet arranges for the Dumb Show, Claudius excuses himself and prays,
O wretched state! O bosom black as death!
O limed soul that struggling to be free
...Help, angels. Make assay.(3.3.67-69)
After listening to Claudius, Hamlet cannot kill him as he prays because Claudius will go to heaven as a martyr; so, Hamlet plans the king's death for later.
The death of Gertrude - After she feels her shame for having married her husband's brother so soon after his death, as well as for her adulterous affair with Claudius before her husband's death as Hamlet berates her--
Such an art
That blurs the grace and blush of modesty,
Calls virtue hypocrite, takes off the rose....(3.4.42-44)
To atone for her sins, Gertrude tries to save Hamlet in the final act as she drinks the poison meant for Hamlet.
The death of Laertes - Because of his love for his father Polonius and his sister Ophelia, Laertes allows himself to be drawn into the dastardly plan of Claudius to slay Hamlet. During his duel with Hamlet, the poison rapier impales him, and he realizes too late that
The foul practice
Hath turned itself on me. (5.2.296-297)
The death of Claudius - When the wicked Claudius calls out for help after Hamlet touches him with the poisoned rapier, Hamlet, angered, shouts,
Here, thou, incestuous, murd'rous, damned Dane,
Drink off this potion. Is thy union here? (5.2.304-305)
- Gertrude -