Card Combat System Based on Stone/Paper/Scissors

I would probably limit the icons to three types. Five different icons would lead to confusion and possibly drive off potential players.

Also I would make the icon types more concrete than "Spiky or Slimy". Personally I would use Cut, Thrust, and Pummel.

Cut beats Thrust (Essentially a Parry)
Thrust beats Pummel (Speedier)
Pummel beats Cut (Forceful)

These can be done in varying amounts and combinations much like you described, though they are more concrete.

As far as more than one pirate fighting at once, I would simply make it a "Last man standing" type game. If the Pirates deafeat the cannibals, well, "There's only room for ONE captain on THIS boat!!!"

This way each type canels out 2 other types and is canceled out by 2 types, giving the players more choice as to which cards they can use.

In each group you have 3 sub types. 1,2,3 (for a grand total of 9). Each sub type specialises in beating one of the main type (A,B,C). 1 beats A, 2 beats B and 3 Beats C.

So in Group A you have A1,A2,A3. A1 beats Any of A. A2 Beast any of B A3 beats any of C.

If you have a marginal victory (A2 vs B1) where one side has a double dominance and the other has a single dominance and a single dominated type then the A2 player would suffer moderate damage but still beat the B1 player.

If there is a tie for a double beating (eg A3 vs C1) then lots of damage on both sides and the outcome is very uncertain (essentially a tie with a random decider).

If it is a double victory (A2 vs B3 or B2) then a total victory occures and little damage would be done to the A2 player.

All this is just summing the victories of the two types (ABC and 123) to give either a single success or double success or tie.

Example:
A victory in a type (ABC or 123) gives 1 point.

Round 1:
Adam plays an A2 card and Betty plays a C3 card. Adam gets no points (A beats B and a 2 beats B) where as Betty gets 1 point (C beats A but the 3 beats C).

Round 2:
Adam Plays a B3 Card and Betty Plays a C1 Card. Adam gets 2 points (B beats C 3 beats C) and Betty gets 0 points (C beats A and 1 beats A).

This is probably far to complex for this game, but I though I'd just throw it out in case it gave you ideas.

Rock, Paper, Scissors, Lizard, Spock is a rock-paper-scissors variant that does precisely what you are talking about (each symbol beats two and is beaten by two). With some tweaks to Greg Porter's code you could probably include the two extra symbols. Actually, though, I was plenty happy with the three symbols using Greg Porter's "Infinite Armies" mechanics. Cards have an attack value and a defense value which are strings of RPS symbols that you compare against each other to see who does how much damage to whom.

Forget Rock-Paper-Scissors... Here's a 25 outcome variation:

Rock, Paper, Scissors, Gun, Dynamite, Nuke, Lightning, Devil, Dragon, Alien, Water, Bowl, Air, Moon, Sponge, Wolf, Cockroach, Tree, Man, Woman, Monkey, Snake, Axe, Fire, Sun.
http://www.umop.com/rps25.htm

Explaination of what beats what here:
http://www.umop.com/images/rps25_outcomes.jpg

Players will have a hand of 'Action' cards, as well as one or more 'Item' cards face up in front of them. Each player will simultaneously place 1-3 Action cards face up onto one of their Item cards.

Both Action and Item cards will have a single symbol on them.

The outcome of the fight is determined by whoever beats the most symbols on the Action cards, not the Item cards (i.e. if I have a 'C' Item and you have a 'B' Action, it does not count as a 'Hit', but if I had a 'C' Action, then your 'B' Action would count as a Hit)

Thus, if a player has only one Item, enemy players will have at least some idea of a card they should not play (i.e. if I have an 'A' Item, you would not want to play a 'B' Action, and it means I would be safer in playing a 'C' Action etc...). But if I had more than one Item, enemy players will not know which Item I will 'Use' (play my Action cards onto).

Yes, I too like the combat system in Fury of Dracula.

I used a 3 S/P/R patern for a game. However I used a system where you needed 2 of the winner to remove 1 of the looser. It also had a rule that if 2 or more of the loser was included then it took 3 of the winner to remove the 1.

For example:
If you had 1 Scissors, then I would need to have 2 Rock to beat you. No matter how much Paper I had I still could not win.

If you had 2 or more Scissors (say 6), then I would still only need 3 rock to beat you.

This was a hex tile placing game and used proximity to determine what threatened what and which tiles were removed. But it could apply to the number of cards put out.

So if Player 1 put out 1 Rock card and 2 Scissors cards. Player 2 might only need to place 2 Paper cards to eliminate Player 1's Rock.

To eliminate imposable placements I made all tiles, regardless of the owner, able to be used to remove a tile. So in the above example, ig you include this rule, Player 1 could not place the 2 Scissors out, without looseing his Rock card (but if he played 2 scissors tand 2 rock this would be ok, but player 2 would only need 1 Rock to elimiente the scissors - 3 is needed).

Speaking of cards...

...I forget if someone here told me where to find it, but here is a site where you can download a MtG-style card maker and use it for your own purposes:

http://mtglair.de/editor.html

At the very least, you can use it to create and playtest your own cards.