When you make an attack or damage roll that is improved by your Sacrifice feature, and the attack reduces an enemy to 0 Hit Points, you don't take Radiant damage from using the feature.
Sacrifice Foe
Raw data
{
"name": "Sacrifice Foe",
"level": 7,
"__prop": "classFeature",
"source": "ValdaSpire24",
"entries": [
"When you make an attack or damage roll that is improved by your Sacrifice feature, and the attack reduces an enemy to 0 {@variantrule Hit Points|XPHB}, you don't take Radiant damage from using the feature."
],
"className": "Martyr",
"classSource": "ValdaSpire24"
}