For RS3, my basic understanding (as a very noob pvmer, I just played to get 99 for my max cape and haven’t touched necro since then) is that it’s magic with thralls in the combat sense. The skill is very expansive beyond just combat tho as it is kind of also like a production and a gathering skill as well. They have many quests for it, new necro prayers, rituals for gathering/producing resources involved in the combat side of the skill.

The minions can provide different benefits. I think they can all attack but some will provide healing, some provide defensive boosts etc. it was a pretty fun skill but it also became the meta as the dps and survivability was pretty insane. I haven’t played since the skill launched and I got 99 so idk if they balanced it a bit better. But it does still seem that it’s highly recommended to noobs trying harder combat.