Inferno faction discussion.

Of course. Attacking with claws and whips is the most likely option.

A succubus, and possibly a tormentor, can throw fire streams or fireballs.

That's the correct way. Morning, you misunderstood me again ;). But "fire spheres" (from the description of succubi in "Heroes 5") are the prerogative of demonesses, so tormentors will most likely throw bones that they grow at the right time. However, if succubi don't use ranged attacks, fireballs may "pass on" to tormentors :).

Well, I didn't know about the specifics of monster spawning, but can a breeder simply steal mana without creating imps afterwards?

attack a second time after the enemy's attack

Another example taken from KB (see Orc Veterans).

By the way, if succubi don't use ranged attacks, then perhaps demons will be left without ranged units altogether, as Drakkosha suggested. This would be another example of the uniqueness of factions. But then the units should have high speed, although they will be powerless during a castle siege :(.