Majin Buu (Ancient, Form Unspecified) → Life-Forms on Planets Destroyed by Ancient Buu
The Supreme Kai states that ancient Buu's destruction and slaughter turned hundreds of planets into dead worlds. The number of planets is not a death toll, and the number of victims is unknown. Because it is unknown how much of the periods in Buu's various forms the report covers, the record is not limited to his Pure or Good forms. This group record concerns the life-forms on those planets and does not include the separately treated North and West Supreme Kais. The original text does not establish whether the two incidents belong to the same continuous rampage or whether their reported victim ranges overlap.
SourceChapter 445 — A Terrifying Mystery (Japanese: 恐るべき謎)Full Color Majin Buu Arc, Vol. 2 · Akira Toriyama / Shueisha
Additional sourceChapter 508 — Kid Buu (Japanese: 純粋の魔人ブウ)Full Color Majin Buu Arc, Vol. 7 · Akira Toriyama / Shueisha