Newbie Questions

[Taqwus]

Regarding Bogus and company --
If memory serves, the mage repeatedly summons Phantasmal Wolves, Bogus tends to charge and lay waste with his Wraith Sword, and the others tend to matter much less.
Bogus comes with a wraith sword -- a two-handed weapon that drains life from its victims, so that if he fights living troops he simultaneously heals and reinvigorates himself while dishing out damage. Even against nonliving troops, he regenerates anyway as a Troll Raider but in that case he can be exhausted. His hit points are high, although not astronomic; if he gets Heroic Toughness (extra HP) he can have a LOT.
The magic of either undead Ermor theme is on the limited side, usually; death, death, more death, and low-powered randoms except on the pretender, until perhaps you reach Tartarians or use your pretender to summon elemental royalty etc. Disintegrate, Rigor Mortis, Nether Darts (req Astral), Shadow BLast, perhaps even lammashastas (a death rarity in that they fly -- but be warned that they'll attack you too) may help. If you can bring in multiple death mages repeatedly casting Drain Life (plus there's a two-handed banner that can be used to cast this) you should also be able to hurt them very badly. Bringing along a Totem Shield so that the troll gang will all end up Cursed may help as well; that'll bring their chance of afflictions to something more normal. Summons-wise, be warned that the wraith sword means that Bogus will have little difficulty hitting ethereal units.