A 17-year-old boy told a court how he was slashed in the face and hand by a man later described as a "mass stabber" as he traveled home from a theme park. Isaiah Idris was on a Docklands Light Railway service in London when Anthony Williams allegedly drew a knife on him.

Williams is facing 14 charges of attempted murder for alleged attacks during a Halloween weekend "rampage" in late October and early November last year. The charges include ten on a DLER train from Doncaster to London on November 1, and four others starting the previous evening. The court has heard Williams denies the attempted murder charges but admits 12 counts of wounding with intent and two of attempted wounding with intent.

Idris had spent the day at Thorpe Park in Surrey on October 31. He became the fourth person allegedly attacked by Williams as the train pulled away from West Silvertown station in east London in the early hours of the following morning. "When the train started moving, it was only a couple of seconds after that he slashed my face," Idris told an officer during a police interview played to the jury. He initially did not realize he was injured until a woman pointed out the blood dripping from his face.

Idris, who had a heavily bandaged right hand, recounted how Williams approached him, pointed a knife at his chest, and asked, "Are you beefing with the devil?" After Idris denied this, he said Williams sliced him again, and he blocked the blow with his hands.

Witnesses described seeing the defendant acting erratically on another train on October 31, muttering, "I'm going to do it." Another passenger, Ethan Daniels, noted someone playing Halloween music from a mobile phone and talking to himself, saying, "I'm the baddest. No one is as bad as me." Daniels stated he avoided eye contact due to fear for his safety.

CCTV footage of an earlier incident at Ritzy Barbers in Peterborough was also shown to the court. It depicted Williams standing outside the shop, making exclamations before taking a knife from a rucksack and entering, causing people to scatter. The owner's neighbor called the police after being shown the footage.

The attacks reportedly began on the evening of October 31 when a 14-year-old was allegedly knifed on a footbridge in Huntingdon, with two men attacked nearby shortly after. Idris was then targeted on the London train before Williams allegedly returned home, and later caught the DLER service for the "mass stabbing." Jurors have seen footage of passengers fleeing Williams, while others reportedly showed bravery by confronting him. Some witnesses reported Williams rambling about the "devil" and "power" on the train, warning, "Everyone's gonna die today."

Prosecutor Chris Paxton KC told the jury that Williams has "some mental health issues which may or may not become relevant during this trial." He added that there was no dispute about who committed the attacks, as Williams accepts carrying them out. The key issue for the attempted murder counts, the prosecution contends, is Williams' intention to kill.

The trial continues.