WARNING: The following contains spoilers for The Amazing Spider-Man #54.LR by Nick Spencer, Matthew Rosenberg, Federico Vicentini, Takeshi Miyazawa, Scott Hanna, Erick Arciniega & VC's Ariana Maher, on sale now.
Spider-Man has been in a war with Kindred and ended up pulling all his close allies into the battle. However, while Kindred has Spider-Man in his lair, the other Spider-Totem members have been on their own. They ended up turning into monsters, went into the Astral Plane to fight Spider-Man's most demented memories, and now Sin-Eater is hunting them. It was during their battle with Sin-Eater that they met their match. The villain had the powers he stole from Morlun, and there was no way the heroes could beat him. Thankfully, Madame Web stepped up and showed them how to beat a powered-up Sin-Eater.
Spider-Girl, Silk, Miles Morales, Spider-Woman, Spider-Gwen, and Madame Web fought a Morlun-powered Sin-Eater and realized quickly they had no chance. Spider-Woman quickly figured out he had Morlun's powers, and the group needed to think quickly. Luckily, Madame Web stepped up. Spider-Gwen said she wished they could see the future and find a way out, and that is when Madame Web said to be careful what you wish for because her visions are not always right.
She stepped forward and said that she misunderstands her own visions sometimes, and there is always a risk because an unforeseen thing could change the future. Sin-Eater had Miles down, and Madame Web told him to let him go because she was the one he wanted. Sin-Eater aimed and fired point-blank into Madame Web's chest, cleansing her of her sins and stealing her powers for himself, which proved to be his biggest mistake. Madame Web was specifically chosen, and there were very few individuals who could have taken on the role of the clairvoyant member of the Spider-Totem. Cassandra Webb chose Julia Carpenter to carry on the role, knowing she had the mental awareness to decipher visions of the future.
Sin-Eater is not mentally capable of that task. The second he took her powers, he gained the ability to see the future, but as it was with Julia, it came in bits and pieces and fragments, and without the knowledge of how to piece it all together, it began to drive Sin-Eater mad, taking what he saw literally. This included visions of Kindred sitting down at a table for what looked like dinner with Spider-Man and Mary Jane Watson. Then he saw that Kindred was, in fact, Harry Osborn, something that shook Sin-Eater to the core. He finally aimed his own gun to his head and cleansed himself, ceasing to exist. As Kindred said, you can't kill what's already dead.
The powers of seeing the future are too much, at times, even for someone as powerful as Julia Carpenter. Before Doctor Octopus killed Spider-Man and became the Superior Spider-Man, Julia saw every point in the future in a split second, sending her into a coma, where she remained for a full year. There have also been many times that Madame Web had misread the future. There was no way that someone like Sin-Eater, a zealot at best, could have dealt with this power, and Julia knew it. She sacrificed herself for the greater good, and it consumed Sin-Eater with the hatred, fear, and paranoia of knowing what was coming and that his mission was for nothing.