Acceptance - S4-E4
Continuity mistake: The second time Hiro goes to the rooftop and tries to save Tadashi he has ink on his face from stopping the photocopier from working. However when we cut back to him from Tadashi the ink has vanished, then when we do get the next shot of him the ink is back on his face again.
Once Upon A Time In Texas - S4-E8
Continuity mistake: While talking to Claire outside the diner, Noah comments that he's looking forward to seeing her at the Homecoming game. But in season 1, Noah knew Sylar was going to try and kill Claire at Homecoming and had forbidden her from going.
Continuity mistake: At the beginning of the episode, when Tracy is talking to the waitress and freezes her mug, the position of the mug changes in her hand between consecutive shots.
Continuity mistake: Episode 4.18, "The Wall" - The dried blood on Claire's neck from when she was shot toward the end of the previous episode keeps disappearing and reappearing throughout the scenes at the Carnival. (00:35:00)
Continuity mistake: (S04e18) Claire has red nail polish when she is in the house of mirrors, however, when she is outside talking to Samuel it is clear nail polish.
Chosen answer: It's not been made 100% clear. It was originally assumed that he actually consumed part of the brain, but this has turned out not to be the case. Sylar has been shown all along to have an instinctive knowledge of how things work and how to fix them - this is his actual original power and the ability that made him an exceptional watchmaker and repairer. It appears that he uses a similar process when acquiring new powers - he exposes the brain of the target, allowing him to examine it and determine how their power functions. He can then apply that knowledge to his own brain, allowing him to replicate the ability in question.
Tailkinker ★