DnD thoughts: Can the game support all ranged parties without losing sophistication?

I think it is uncontroversial to say that melee combat is in many ways crucial to sophisticated DnD 4e combat. Shifts, attacks of opportunity, aiding another in combat, bull rushes, grabs, defenders (with the possible exception of swordmages), and to a lesser extent forced movement all provide an exciting mix of options for combat. Stealth and many classes do work well or even exclusively at range, but in many ways they work best in concert with melee allies.

This is of course a legitimate choice on 4e’s end. Dungeons and Dragons, as the name implies, is fantasy oriented. However, for those of us that like the system but prefer steampunk, pulp, modern, or sci-fi settings the melee orientation can be limiting. Dune and Lensmen both show that these settings can work in a melee oriented way, but it would be nice if that was an option, not a requirement.

So what would it take to get DnD as robust for a primarily ranged party as it is for a mixed or primarily melee party? First off, additional defender classes/alternate builds for existing ones), but this can’t just be about defenders, many of the melee options discussed above are viable for a range of classes. To really get there, I think cover-based fighting is the ranged equivalent of attacks of opportunity.

By this, I don’t mean cover as a technical term in DnD, I mean the general feel of cover based first person shooters and the like. Here’s a broad outline of what I’m thinking after the cut.

1. This is the main addition, a new status called exposed.
   1. To be exposed to an enemy, that enemy must have line of sight on you.
   2. There’s a range limit for exposure, probably 5 squares by default. Possibly half of the normal range for your weapon. As with attack of opportunities and threatening reach, a player would know what the threat range is here.
   3. Having partial or total cover or concealment from that enemy means that you are not exposed. The source of the cover or concealment doesn’t matter, smoke, invisibility, what have you.
   4. Being prone also means that you are not exposed.
   5. As an exception to the rules above, if you grant combat advantage to that enemy and the enemy has line of sight you are exposed.
2. Characters can make ranged basic attacks of opportunity against exposed characters that [provoke attacks of opportunity (see point 3 for what provokes]. Being able to exploit others exposed status requires spending a move action provide covering fire.
   1. I’m stealing this mechanic from X-Com where preserving a certain number of action points was a pre-requisite to taking shots at the enemy during their turn.
   2. As soon as an enemy sees you they’ll know that you’re providing covering fire.
   3. However,  if say you’re hidden at the time they may learn this to late.
   4. I think sacrificing the action is key to keeping this from getting annoying. Calculating cover for all ranged weapon toting enemies, even with a range limit, is too computationally intensive for a non-computer game. I don’t want granting cover to require sacrificing your attack, but the cost needs to be significant so a minor probably doesn’t cut it.
3. [Characters provoke ranged attacks of opportunity under the following conditions]:
   1. [Characters do not provoke] if the [attacker] is vulnerable to melee attack of opportunity for making the ranged basic attack. I think this is important to be fair to melee-types and also seems sensible. I don’t know if it should be hardcoded to work when an attack of opportunity would typically be an option or if it should specifically overrule abilities that let you make ranged attacks without [provoking] attacks of opportunity.
   2. [Characters provoke when they take] a standard action, including attacking the enemy in question. This is rather different than a melee attack of opportunity because it is your positioning, not letting your guard down, that [provokes].
   3. [Characters provoke if they take a] move action and [are] still exposed at the end of that move action. [Becoming exposed during the move does not provoke, but means that any subsequent moves or standard actions have the potential to provoke].
   4. Shifts are not an exception to the move action rule. Moving slower and more carefully [still provokes].
   5. Running or crawling does not [provoke]. You do not have to run your full distance, what matters is that you’re moving fast and taking the penalties for doing so.
   6. Normal limits on number of AoOs per turn apply.

I’m not going to try to think through all the defender rules, there’s a range of obvious possibilities: your shotgun type ranged basic attacks with stopping powers, your automatic weapon type doing nasty at-wills as ranged basics, a heavy weapons user that adds an extra stat to ranged basic attacks, a highly mobile defender that can provide covering fire as a minor, one that can ignore adjacent cover when calculating whether an enemy is exposed.

These rules are pretty rough, they’d probably take a fair amount of debate and play testing to get right even before figuring out the defender roles. That’s why I’m posting them here. If anyone’s interested in playing with working them out, let me know. If you go on to use them on your own treat this as in the creative commons, give me credit but feel free to modify them and distribute them for free. [I figure my next step is to make up some monsters that use these type of rules and see how they play.]

[Update: A few changes to improve clarity, I hope.]

[Update 2: Rethought somewhat how moving and provoking would work.]