For the achievement, see Kal'gerion Notes (achievement).
Kal'gerion notes detail

The Kal'gerion Notes are a series of journals found while Dungeoneering in Daemonheim. Players may find parts of the notes once they defeat certain bosses in the dungeons. The notes detail the ways and works of the Kal'gerion demons which were summoned to Gielinor in the late Fourth Age by the Mahjarrat Bilrach. Players can view these, along with the rest of their Dungeoneering journals, by talking to the Dungeoneering tutor outside Daemonheim.

Notes Obtained from On floor
Part 1 To'Kash the Bloodchiller Floors 9-11
Part 2 Har'Lakk the Riftsplitter Floors 18-29
Part 3 Bal'lak the Pummeller Floors 33-35
Part 4 Yk'Lagor the Thunderous Floors 45-47
Part 5 Kal'Ger the Warmonger Floors 57-60
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