Sunday Times Teaser 2945 – Infernal Indices

by Stephen Hogg

Published March 3 2019 (link)

The above is the size of the evil multitude in the last “Infernal indices” novel “A deficit of daemons”.

“Spoiler alert” — at the end, the forces of good engage in the fewest simultaneous battles that prevent this evil horde splitting, wholly, into equal-sized armies for that number of battles. The entire evil horde is split into one army per battle, all equally populated, bar one which has a deficit of daemons, leading to discord and a telling advantage for the forces of good.

How many battles were there?