LOGAN, IA -- An Iowa teenager testified that when he killed his 5-year-old foster brother, he was in a fantasy world and thought he was killing a goblin.
Cody Metzker-Madsen told a western Iowa courtroom that he visits a world only he can reach whenever he plays with someone. He said he didn't realize until afterward that what he thought was a goblin was actually his foster brother, Dominic Elkins.
"I loved the little guy, I would never hurt him," Metzker-Madsen said during his testimony that lasted more than 40 minutes Wednesday.
His lawyer is using an insanity defense, The Des Moines Register reported.
Authorities say Metzker-Madsen killed Dominic last year while the two were playing outside of their home near Logan. Metzker-Madsen was 17 when the boy's body was found at the bottom of a ravine.
An autopsy showed he died of blunt-force head injuries and drowning.
Metzker-Madsen said the two were playing a game that involved Roman mythology in the backyard. He said he went to his own world, which has slightly different colors and smells than the real world, and saw an army of "green, ugly little creatures."
He said the goblins were fighting people he knew and that the scene was similar to a video game he played.
He said he didn't know it was Dominic when he pushed his head into the water at the bottom of the ravine while hitting him with a brick.
Prosecutors noted that Metzker-Madsen provided different stories for why Dominic died and was able to lead his foster family to the body. During cross-examination, he said he told varying versions of his story based on symbols he saw on top of people's heads that indicated whether he could trust them.
Metzker-Madsen also faces an assault charge after authorities say he bit a Harrison County jailer on Tuesday. He testified in court that he only remembers "bits and pieces" of the incident.
His attorney said he couldn't comment on the additional charge.