Inferni are Summoner Grisha who can manipulate fire.
Inferni Term Timeline in Shadow and Bone
The timeline below shows where the term Inferni appears in Shadow and Bone. The colored dots and icons indicate which themes are associated with that appearance.
...it’s time to get ready for the demonstration. She leads Alina backstage, where they watch Inferni summon flame and Squallers and Tidemakers create glitter and waves. The Darkling comes up behind... (full context)