Jeff wrote:Only Fighters are allowed to make multiple attacks, one per HD, and only against man-types, correct? Can they make multiple attacks against heroic/super-heroic man-types?
First part: The DD rules explicitly say fighters have multiple attack rolls each turn versus normal-types (normal types is broader than only man-types). Whether non-fighters should also get multiple attack rolls per turn is a matter for the referee to decide, but consider: an enemy/NPC cleric or magic-user is effectively a monster
and monsters get one attack roll per HD versus normals. So from that perspective it's plausible that non-fighter players should too. Considering also that Chainmail explicitly gives Wizards multiple attack rolls per turn versus normals, I think it is very plausible.
Second part: No. By the book, heroic combat (that is, attacks against heroic-types) is generally resolved with one attack roll per turn. There are a few exceptions (which are generally the multi-headed monsters).
Jeff wrote:Are multiple attacks mandatory? Or can the Fighter choose to make 1 attack at full HD?
By the book combat is dichotomous; it is either
heroic, depending on what you choose to attack. OD&D (and thus DD) inherit this directly from Chainmail where you would use either
the mass combat/man-to-man rules or
the fantasy combat table to resolve a combat.
You might still have a choice if, for example, you encountered an Ogre and ten Orcs. In that scenario you could choose to engage in heroic combat (one attack roll versus the Ogre), or in normal combat (N attack rolls versus the Orcs). But an individual figure can't--by the book--engage in both normal and
heroic combat within one turn. In Chainmail terms, that would be like trying to resolve part of your attack routine with the mass combat/man-to-man rules, and part of your attack routine on the fantasy combat table.
Jeff wrote:Can the Fighter make 2 attacks at 1/2 HD? Or 3 attacks at 1/3 HD? (see where I'm going with this)
I see where you're going
That kind of thing isn't "by the book" but it would make a fine house rule, for sure.
Jeff wrote:Does the Chimera get 3 attacks against super/heroic types?
Yes, the Chimera has three attack rolls in heroic combat (and, because it is 7 HD, would have seven attack rolls in normal combat). There are other multi-headed (or multi-armed) monsters that function this way as well. In general, wherever DD attributes multiple attacks to a monster type, it means multiple attacks in heroic combat
(and this is stated in the explanation of monsters
Hope this helps