An abstract being self-described as the embodiment of entropy, the Griever at the End of All Things was a mysterious creature who claimed her purpose was to witness the last light fade from the edge of Eternity and grieve for everything that ever was and was ever meant to be. She commanded strange creatures called Endlings. The Griever started following the Future Foundation during their journey to create and add new universes to the Multiverse. She repudiated their mission, claiming they overstepped their purpose.

She patiently waited to strike until Franklin Richards was depleted of his ability to create new universes. She confronted the Future Foundation and killed the Molecule Man in the process of creating a chain reaction that triggered the destruction of the hundreds of realities the Future Foundation had helped create. The Future Foundation managed to escape, and the Griever cornered them in the universe where they decided to take their final stand. After defeating the heroes, Mister Fantastic taunted the Griever, claiming she would be defeated if she confronted the entirety of the Fantastic Four. Angry that Richards would question her power, she delivered Richards a Transmaterializer to use to transport the Fantastic Four. To the Griever's surprise, Richard didn't just transport the remaining original members of the team but past members as well.^[1]

While their allies kept the Griever distracted and protected the Future Foundation, Reed and the Fantastic Four fought the Griever. Reed realized early on that the Griever couldn't travel to different realities under her own power and had to rely on her ship to do that. He told Johnny to destroy the Telepods of the Griever's ship until there was only one, though the Hulk secretly performed the task but was willing to give Johnny the credit. Reed then confronted the Griever on her inability to move through realities as well as the fact that she was unable to create anything. After Reed threatened to strand her in the reality where their fight was taking place by destroying the last remaining Telepod, the Griever finally backed down and returned to her native realm but swore vengeance before leaving.^[7]

Shortly after Franklin Richards became fully depowered, the Griever returned. Chasing away the refugees of the worlds she had destroyed, they used a pathway through the Forever Gate to reach the Earth.^[8] With the Fantastic Four unable to shut down the Forever Gate due to the constant stream of refugees, the Griever eventually used it herself to arrive at the planet. When she chased after Franklin Richards to defeat him, he used a remotely-piloted armor to lure her into 4 Yancy Street, the Fantastic Four's headquarters that housed additional pocket dimensions inside. Mister Fantastic folded the building into itself in an attempt to trap the Griever within its dimensions, but she managed to escape due to being an abstract concept.^[3] Defeating the Fantastic Four and their allies, the Griever attempted to force Mister Fantastic to teach her how to use the Forever Gate so that she could use it to link up to every place and time period and fulfill her sole purpose of destruction. The Silver Surfer managed to stall the Griever, but she defeated him, prompting him to hand over the Ultimate Nullifier he had acquired on Mister Fantastic's behalf to Franklin Richards, since he was the only person with the necessary understanding of the fabric of the universe to use it against the Griever. With the Griever cornered, Mister Fantastic came up with the idea to offer her the chance to use the Forever Gate for a one-way trip into the future to the natural end of the universe so she could finish it off, and she agreed.^[9] However, her destination ended up being the Reckoning War,^[10] which ended with all of reality being saved.^[11]

Appearing as an "angel" to the Wizard, she sent the villain to eliminate the Scarlet Witch and her brother Quicksilver, but the twins prevailed.^[12] Not long after, the Griever, armed with the Edge of Reality, launched a personal attack on Lotkill. The Scarlet Witch unleashed the power of the True Darkhold within her but even this was not enough and the Griever slayed her with a blast. Using a device from the Stranger, the Griever selectively targeted Lotkill to raze but was met with resistance from Wanda's siblings, Quicksilver and Polaris, who used iozium to fight her.^[13]

The Griever is an immensely powerful abstract being. She destroyed the bonus universes Franklin Richards and the Molecule Man had created for the Eighth Cosmos. She was able to kill a distracted Molecule Man and defeat a greatly weakened Franklin Richards.^[1] She was able to kill the Scarlet Witch, even after Wanda had unleashed the power of the True Darkhold, with a single blast from her forehead.^[2]

Reliance on Technology or Items: The Griever cannot move through realities or time on her own and must use technology or the Edge of Reality.^[4][9][6] It is possible to indirectly defeat her by destroying her means of travel.^[7]

Inability to Create: The Griever cannot create anything herself since she is the embodiment of destruction and entropy. While she is knowledgeable in using technology, she does not appear to understand its functions as she failed to understand if technology is broken but repairable or is completely unsalvageable. She is also less than immediately capable of turning her universe-destroying power on individuals, analogized by Reed as a person being less capable of destroying a single germ rather than sanitizing an area.^[7]

Ultimate Nullifier^[9]

Iozium: A special material transmuted from low mysterium, iozium is effective against the Griever.^[6]

Transmaterializers

Edge of Reality^[2]

Her very own ship that is capable of traveling into different realities.

• The Griever claims she is "Entropy" and "heat death."^[1] Her relationship with the other cosmic being known as Entropy is unclear.

• The Griever has a feeling she will see Franklin Richards at the end of time.^[9] This references the idea that Franklin will survive to the end of the Eighth Cosmos and then go beyond the end of time to the Ninth (similar to Galan (Galactus), Moridun (Omnimax), etc.).^[14][15]
• The Griever calls the end the "Truth" and she also uses the term "Quiet Math."^[16] This may be a reference to the "Quiet Math"/"Silent Truth" from Sir Isaac Newton, who calculated mathmatically (the Quiet Math) that the world will end in 2060 AD and concluded that the end of the world is inevitable (the Silent Truth).^[17][18]