Chaos Necromancer benefits by having exponential ATK increase based on the number of monsters cards in the Graveyard x 300. Dark Necrofear can banish this card and another 2 Fiend-type monsters, from the Graveyard in order to be Special Summoned.
Since Fabled Gallabas is a LIGHT attribute Fiend-type monster, if you have used it in conjunction with other DARK attribute Fiend-type monsters, you can potentially Special Summon Black Luster Soldier - Envoy of the Evening Twilight by having the equal amount of LIGHT and DARK Fiend-type monsters in your Graveyard. Similarly, you can banish 1 LIGHT and 1 DARK monster from your Graveyard to Special Summon Darkflare Dragon.
Discards for cost
Destroys your opponent's face-up Monster Cards
This card's description is incorrectly translated in italian. it says "discard this card" instead of "discard a card"
Current DEF. If it is Original DEF the card would have said so.
This card seems pretty dumb, until you realize that most meta decks revolve around monsters with less than 1500 def. Wipe out a field of Fur Hires by discarding ganashia's and just watch as your opponent does that thing where they just stop dueling in hopes that you'll disconnect before they time out
There's quite a few cards that can clear a field of Fur Hires honestly. It's not hard as long as you can get past Wiz and the small amount of backrow they run. I've run through their fields enough times with Hydrogeddon on my second account, lol.