An Australian and a British teenager allegedly discussed strapping explosives on a kangaroo, daubing a symbol of Islamic State (Isis) on it and setting it loose on police officers.
Sevdet Besim, 19, was one of five people arrested last April as part of an alleged plot in Melbourne during Anzac Day commemorations for fallen Australian and New Zealand soldiers.
Besim is accused of discussing his plans online with a British boy, who was 14 at the time.
A court in Melbourne heard that Besim wrote that he would "love to take out some cops".
The alleged plot emerged from a prosecution summary of internet communication on March 20 last year. The court was told that Besim and the British boy discussed the suggestion that a kangaroo could be packed with C4 explosive, painted with the Isis symbol and set on police officers.