Mike Pikos, 18, came before Melbourne Magistrates Court on Sunday morning but was not required to speak during the short hearing.
Magistrate Steven Raleigh was told it was the teen's first time in custody and he would be a vulnerable prisoner due to his age and appearance.
No other information was given during the brief session and there was no application for bail.
Police allege the victim, a 22-year-old man, was one of several passers-by who stepped in to intervene after a group of teens set upon a 14-year-old boy at the Mernda train station, in Melbourne's northeast, on Friday night.
The man tried to walk away with the boy but was subjected to a "savage" attack involving punching, kicking and the use of blades, Homicide Squad inspector Nigel L'Estrange said on Saturday.
The victim suffered life-threatening injuries and was treated by paramedics but died at the scene.
Four male teens - Pikos, two 17-year-olds and a 16-year-old - were arrested.
The 16-year-old, from Whittlesea, a 17-year-old from Geelong and Pikos were all charged with murder and armed robbery.
A 17-year-old from the City of Yarra is under police guard in hospital and is yet to be charged.
"This is just a tragic situation where our victim here is just a good Samaritan who was trying to do the right thing," Det Insp L'Estrange said.
"He's intervened, tried to protect this 14-year-old schoolboy, hasn't been aggressive at all, tried to remove him from the scene, and as a result of his interaction, he's now lost his life."
Health Minister Mary-Anne Thomas said her thoughts were with the victim's family while pointing to recently introduced youth crime laws that could result in juvenile offenders being dealt harsher punishments for serious crimes.
But opposition police spokesman Brad Battin said the incident highlighted Labor's failure to tackle the issue and remove machetes from the streets.
Pikos was remanded in custody and will return to court on June 24.
25°C