I've been lurking for a little while and seeing a few threads about card-based combat systems I thought I should put my ideas out there for your perusal.

The concept here is a combat system where opponents whittle away at each others defences until eventually a hit gets through. I hate the way that in a lot of RPGs your PCs come out of a fight half dead yet consider it just another day at the office. This system should allow firstly for combat against lots of weaker enemies without taking a scratch, but always there is the worry that if they do slip up they will seriously regret it, secondly for detailed and prolonged dueling with a well matched opponent and thirdly for a prolonged fight where the PCs team up against a stronger foe. Using cards means that all of this is possible with minimal book keeping and reasonable speed.

Each round every player involved in the combat draws a hand of cards. The size of your hand is determined by your Stats and Skills, probably 1-5 cards for each so 2-10 cards total. Actually, 2 cards isn't enough, I think 4 is probably the minimum The idea is that the hand of cards you are holding tells you how well placed you are for the rest of the round, you can start planning straight away.

Each player then plays a card face down for initiative, all card are revealed simultaneously, highest card plays first. This means that you can rush in to get the first hit, but that will reduce the decent cards in your hand for the rest of the round. You can be cautious and play a lower card hoping to defend the first attack. Of course bluffing and miss-direction are possible too.

The player with the initiative makes his attack by playing any card in his hand up to the value of, for example, Reflexes+Sword. So while higher cards are better, you have to have the skill to use them.

The defending player then plays a card in defence. The card has to be equal to or greater in value than the attack card, so if the attack card played was higher than the defenders ability at dodging or blocking then he will not be able to defend.

If the defender can not play a single card high enough to parry or dodge the attack then he can play multiple cards to hold it off. This however lessens his options for the rest of the round.

If the defender does fend of his opponent then he can immediately play a higher card as a riposte (for some bonus, maybe -1 to his opponents defence) or the initiative passes to the defender.

There are other options:
-Feint. Play an attack card, when your opponent plays his defence you immediately play a second, higher card for your actual attack. The first attack and defence cards are effectively ignored.
-Hold back. Your charcter pulls away and re-assesses his situation as you discard and re-draw as many cards as you wish from your hand. You lose initiative though and if your opponent does the same then a new round starts, hands are drawn back up to full and initaitive cards must be played again to re-engage.
-Face cards could be used as wild cards so effectively they could be played at the score of your stat+skill.
-Suits. I don't want to tie particular suits to particular actions as everyone is fairly limited in what cards they can play anyway. Perhaps give a bonus if you can follow suit.
-Multiple cards of the same value could be played together for multiple attacks or similar.

It is very much still a prototype but I'd be very interested to hear your thoughts.

Well how about that. I thought that this was the first time I had posted here but I just noticed that my post count was sitting at 2! A little investigation and it turns out that two years ago when I signed up I wrote this post: http://www.indie-rpgs.com/forum/index.php?action=profile;u=9728;sa=showPosts, which also talks about the same combat system! Simon C was kind enough to reply but I never saw it. If you are still here Simon, I'm sorry it has taken me two years to see your post!

As for the points Simon raised:
-This system does give a lot of advantage to skilled combatants. Figuring out if it is skewed too much that way will need some playtesting I feel.
-Turn structure is outlined a little better in the post above. However if youever run out of card you imediately draw one more. This give you the ability to try and defend, or even attack if you get the chance, but you are now running on raw luck and skill, tactics are almost completely removed until you can draw your hand back up. Note though that other people have suggested that minimum hand size should be 2 or 3 cards.
-Cards are held in your hands between turns as much to make you spend time discarding the rubbish cards as it is to let you hold on to the good cards. It adds another aspect to the tactics of the game and represents quite well the shifting advantages gained by each of the fighters.

Being one of the people who posted a card-based combat system, I really like it. It seems like you've covered a lot of areas and given a lot of options to the participants of the combat. Card systems seem to have a little more flexibility than dice, since one draw gives you a number of options (color, suit, value) rather than a static number.

I don't know if it's completely solid yet, but it's hard to tell without giving it an actual try. I'd like to see how it holds up under a playtest.

My difficulty in coming up with a system is that I'm trying to model a gunfight rather than a melee which (in my view) has a few more variables, or at least, a different set of variables.

Here's an idea for an alternative.

Fighters pick the number of cards their hand allows. Initiative is played to determine who is first to attack. If you do not wish to get the first attack, you do not have to play anything.

When you attack: you choose a target, pick a new card, make and make your move. You can only play one card except for doubles / triples / quadruples, those can be played as many as you wish on the same turn. Your target picks a card too and defends the same way the attacker attacks. Anyone else who wants to play a card can (I'll call that an interruption) but it does no damage to anyone (and that card is not replaced). Once everyone who wishes played, damages are resolved. And those who aren't attacker or defender get to pick a new card if they aren't at their maximum size. In the great tradition of card games, the next attacker is the one who played the highest card on the previous turn. Ties goes to the defender.

If your attack or defense is twice higher as your opponent, you get to draw a free card (up to your permitted deck size).

I would not restrict which cards people can play because higher stats people already have an easier time doing interruptions and whose larger hand favours getting doubles.

A nice point of this system is that it enables combos where you have a better hand than your opponent, he can't pick good cards and can't attack since control always come back to you. There's no "just luck part". Low cards don't just clutter your hand because you can eventually double them making them decent and you have to manage a shrinking and growing deck, there's no "I finished all my cards so I just rely on luck now".

With this system, two characters would fight a rapid fire series of blows which would results in them getting weaker and having less and less cards until a friend steps in with an interruption and gets his turn in the limelight. Meanwhile, the pool of the previous fighter replenish and he will be able to later interrupt.