Prosecutors of the International Criminal court at The Hague have accused former Ugandan rebel Dominic Ongwen of 70 war crimes and crimes against humanity.
Mr Ongwen has also been accused of ordering his men to kill, cook and eat civilians. Prosecutors used Thursday's confirmation-of-charges hearing to try to convince judges there is enough evidence for Mr Ongwen to stand trial.
They said Mr Ongwen had used schoolgirls as sex slaves, conscripted child soldiers and, in at least one instance, ordered his men to kill, cook and eat civilians. Images shown in the session included a video of shallow graves in the aftermath of an attack. The prosecution is focusing on attacks on four displaced camps housing civilians driven out by the LRA's violence.
His defence is likely to use his past as a former child soldier and kidnap victim as part of a plea for leniency. His lawyers are likely to argue he had a traumatised youth as part of a plea for leniency, the BBC's Anna Holligan at the Hague says.
He is believed to have been a deputy of LRA commander Joseph Kony, who is still on the run. Over the next five days, the defence and prosecution will have a chance to outline their arguments. The judges will then have 60 days to decide whether there is enough evidence to put him on trial.
Mr Ongwen, born in 1975, surrendered in January 2015. He was abducted by the LRA when he was 10 years old and rose to become one of its commanders. He is the first member of the Lord's Resistance Army (LRA) to appear before the International Criminal Court.