A teenager joined a neo-Nazi group after passing a "test" by expressing hatred for Jews and claiming he wanted to provoke a race war, a court heard.
The 17-year-old, who cannot be named for legal reasons, was tested online to see if he was a "worthy" recruit of the so-called Feuerkrieg Division (FKD).
He discussed converting a blank-firing gun and making ammunition in the online forum, Birmingham Crown Court heard.
The youth, from Rugby in Warwickshire, denies preparing for acts of terrorism.
Prosecutor Matthew Brook said the defendant had asked an adult friend for advice on where he could buy a blank-firing gun.
Discussions he had on neo-Nazi group chat forums showed that he was offering "concrete, practical advice about not only converting a blank-firing gun, but making ammunition for it that will 'smash heads"', Mr Brook added.
In another entry read to the jury, he is alleged to have written: "I'm getting armed and getting in shape. I'd urge everyone to do the same."
The teenager was tested by the FKD over his proposed membership of the group and also two private chat groups for UK-based far right extremists, the court heard.
Mr Brook told jurors the group believed in violence, mass shootings and the breakdown of society.
But even before joining, the youth was interested in whether "this was a serious group that could be involved in physical action in the real world, rather than being in his words 'just an online thing', Mr Brook added.
During the test, the youth defined fascism as "the pursuit of restoring the natural order" and said he wanted to provoke a race war.
He also described Jews as "a parasite which must be eradicated", Mr Brooks said.
The youth denies a count of preparation of terrorist acts between April and September last year.
The trial continues.