User blog comment:Crimson and Darkness/Volume 25 discussion blog/@comment-2601:8C:601:5692:6CC6:6C09:CEA1:B2ED-20180321212211/@comment-2601:8C:601:5692:6CC6:6C09:CEA1:B2ED-20180322053628

@ "Happy for new info

I could have posted it on that wiki as well, but was too lazy. Some of it was relevant to this series, the rest just interesting, hence why here. Still waiting to update the wiki overall until TLer finishes updating Volume 1 (from WN to LN version) and moves on to Volume 2. "Nephilim" is a Grigori organization/training center, one that Tobio & co. joins following the events of V1.

@ vanishing welsh

Except for Artemis (and Midgardsormr via Vidar's previously mentioned armor), the others don't participate in the match. I'm not sure, but from the sound of it they're additional members added afterwards (or were reserve members). Interestingly, Orthrus and Hydra (I forget whether Sphinx was included), along with Cerberus and Ladon, are the children of Typhon.