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Erasmas
2013-09-05, 09:27 PM
I have been watching Avatar: The Legend of Korra recently and it got me thinking back to an idea I had had when I watched The Last Airbender. I think that an RPG set in this world would be really interesting and potentially a lot of fun.

Now, understandably... this seems like it could easily be accomplished through a careful selection of classes and setting-specific material (of which you could likely draw a lot of from 3rd Edition's Oriental Adventures, Legend of the Five Rings, or similarly-themed book. However, my mind always comes up short when it comes to combat. In turn-based strategy games - you move, you attack, your opponent does the same... you may hit, you may not and the same goes for your opponent. But to me, one of the crucial things that a combat system based around the Avatar series would need is the constant adaptability of offensive and defensive maneuvers. A water bender may prepare a tendril of water for an attack, only to see an incoming blast from a fire bender and decide to change the water into a downward splashing defense instead. An earth bender might pull up a column of rock as an attack, only to have her opponent deftly slide backwards... to which she could then send a 'slice' a disc out of the middle of her column to send streaking towards them as a secondary part of a combo. Obviously, there would have to be some sort of limit because then every action would turn into a never ending "stack" of interrupt-styled counteractions.

Is there a system that incorporates anything like this? Is this even possible to achieve without becoming too cumbersome?

Morgarion
2013-09-05, 09:40 PM
I think Dark Heresy allows you to borrow an action from your next round in order to defend yourself from an attack.

And, I think the word you wanted was 'reactive', not 'reactionary'.

warty goblin
2013-09-05, 09:46 PM
The original non D20 Sovereign Stone has a system not unlike this. Everybody declares what they're doing, and rolls the relevant dice. This counts as both their initiative and how well they did. But players farther down the initiative order can change their attacks to defense and reroll freely. So if A and B are fighting, A rolls 18, B 12, B can either take the hit and attack A, or reroll their attack as a defense to try to beat A, and entirely nullify the attack.

The spellcasting system also allows for multi-round actions.

kyoryu
2013-09-05, 09:48 PM
Fate could do this pretty well - your turn is spent Creating Advantage representing your power build up, and then you end up using that Advantage for defense rather than offense.

The back and forth invocation of Aspects can also end up with this feel.

Tengu_temp
2013-09-05, 10:29 PM
In Legend of the Wulin, every martial arts technique you know can be used only once per round. Most techniques are used strictly for offense or strictly for defense... But a few can be used for both. Dragon Chi and its ability to turn shock attacks into stat bonuses springs to mind.

For bonus points, it's a system that already focuses on supernatural martial arts, does so pretty damn well, and already has elemental styles in it. All you have to do is homebrew a few new ones.

The Dark Fiddler
2013-09-05, 10:48 PM
I think Dark Heresy allows you to borrow an action from your next round in order to defend yourself from an attack.

And, I think the word you wanted was 'reactive', not 'reactionary'.

Actually, you get one reaction a turn if I recall correctly. Certain talents give you more, but most people just get one a turn.

Anyway, you're probably not going to be looking for a d20 system. warty goblin's suggestion may be the exception, but I've never personally encountered such mechanics in a game. If you really want to stick to d20, but are willing to budge on the style of combat, you might find Mutants and Masterminds more to your liking; it's made for superheroes, but with some skill putting together powers one could definitely emulate bending.

My personal recommendation would be for Fate or FUDGE, though. I actually ran a Avatar game in Fate Core; it only lasted one session but it worked pretty well. All I did was say that anybody who could bend could just make Shooting or Fighting rolls like normal, mixing bending into their description. For any fancy bending stuff unrelated to fighting (e.g. freezing a bridge over water, moving a boulder, controlling a raging fire) I let the players use Will instead. As already stated, the aspects system would work decently for the whole preparing oneself thing.

Rakaydos
2013-09-05, 11:06 PM
In Ironclaw, casting magic is split into "ready" and "attack" actions. If you have a spell readied on the opponent's turn, however, you can use it as part of the "Counterattack" defence.

warty goblin
2013-09-06, 12:02 AM
Anyway, you're probably not going to be looking for a d20 system. warty goblin's suggestion may be the exception, but I've never personally encountered such mechanics in a game. If you really want to stick to d20, but are willing to budge on the style of combat, you might find Mutants and Masterminds more to your liking; it's made for superheroes, but with some skill putting together powers one could definitely emulate bending.


The original Sovereign Stone is very much not D20. The second version ported the game to D20, which made all the mechanics both less flavorful and much more convoluted. I only own it because it was like $10, and it has awesome cover art. I think there's a Pathfinder version now as well, but I have no idea why anybody would want such a thing.

If long out of print RPGs aren't your thing, but the system is interesting, the Serenity RPG uses pretty much the same one. It's sci-fi though, and doesn't include rules for multiple-turn magical effects. I think Margaret Weiss Productions has a newer RPG that uses the same basic dice mechanics, but I haven't ever read it.

Knaight
2013-09-06, 01:06 AM
Is there a system that incorporates anything like this? Is this even possible to achieve without becoming too cumbersome?

I've seen several. The best example of this is probably Burning Wheel, where everyone scripts orders, and orders go off at the same time and interact - essentially, everyone takes their turn at once. However, you script several orders at once, and orders can be dropped from the script to change other later orders mid-round.

Another system I've seen is basically an initiative counting system, where things cost points of initiative to initiate. To use your example, say we have a water bender at initiative 20, and a fire bender at initiative 18.
Init 20: Water Bender draws a large amount of water (takes 3 points of initiative, drops to 17).
Init 18: Fire bender throws a fast attack (connects at 16), initiative drops to 15.
Init 17: Water bender drops the water around themself as a shield.

Generally speaking, with hidden initiatives and random drops what happens is some interrupts, but also cases where someone gets in an attack that connects before their opponent can react. Or, in some cases, someone will go into a defense and just have it completely powered through.

That said: The way I'd probably handle this is with an opposed roll system, and a set of stances. At the beginning of every round everyone takes some sort of stance, which has both offensive and defensive properties. There's some sort of opposed combat roll, and the winner gets their offense off, against the loser's defense.

SiuiS
2013-09-06, 01:16 AM
Board games!

Divided turns. You get three turns you designate as actions a round. You cycle through them. So you pick, say, move, attack, attack.

You move. Your opponent does something you can react to. You can either Defend instead, move out of the way, or stay with attack. Switching should have some penalty, maybe diminished pool on the next action, but the cost of stayin with your choice is being out maneuvered. Unless you picked well, of course.

Slipperychicken
2013-09-06, 01:00 PM
The Avatar d20 homebrew for dnd 3.5 gives bending classes the ability to use Immediate actions to throw up a defense made of whatever element they were using.

Erasmas
2013-09-06, 01:51 PM
Excellent, thank you all for the great responses! It looks like I have some more research to do. Although I am definitely much closer to understanding how I would probably run this system!

CarpeGuitarrem
2013-09-06, 03:51 PM
Tenra Bansho Zero simply lets a successful melee defense roll count as an automatic counterattack. So if you beat your opponent's roll, you deal damage instead of them.

kidnicky
2013-09-06, 08:01 PM
The original Sovereign Stone is very much not D20. The second version ported the game to D20, which made all the mechanics both less flavorful and much more convoluted. I only own it because it was like $10, and it has awesome cover art. I think there's a Pathfinder version now as well, but I have no idea why anybody would want such a thing.

If long out of print RPGs aren't your thing, but the system is interesting, the Serenity RPG uses pretty much the same one. It's sci-fi though, and doesn't include rules for multiple-turn magical effects. I think Margaret Weiss Productions has a newer RPG that uses the same basic dice mechanics, but I haven't ever read it.

Marvel Heroic Roleplaying. A successful defense roll can damage your opponent if you spend a "plot point". So just houserule out the plot point part and you should be good to go.

Autolykos
2013-09-07, 06:54 AM
There are also a few systems that abstract over the attacker/defender roles completely. Shadowrun 3e (or my own system) rolls a contest between the relevant combat skills and lets the winner do the damage. Basically, you *always* attack and defend at the same time, and the better one gets through.
I never really understood why systems separate attack and defense anyway. If I learn to use a weapon, I learn how to attack *and* how to defend with it. When two people are fighting, both are constantly trying to attack (unless one has a really good reason not to).

tasw
2013-09-07, 11:42 AM
There are also a few systems that abstract over the attacker/defender roles completely. Shadowrun 3e (or my own system) rolls a contest between the relevant combat skills and lets the winner do the damage. Basically, you *always* attack and defend at the same time, and the better one gets through.
I never really understood why systems separate attack and defense anyway. If I learn to use a weapon, I learn how to attack *and* how to defend with it. When two people are fighting, both are constantly trying to attack (unless one has a really good reason not to).

I've always wanted to do a home brewed system like that. Never got around to it though.

Anyway to the OP if you dont want all the hassle of making your own system I'd say to go with dark heresy. As previously mentioned it already allows for 1 reaction action each round so you would just have to homebrew up some avatar style reactions for it. Which shouldnt be too tough. The system itself is percentile based so its hard to break too hard as long as you put a little thought into it.

Tengu_temp
2013-09-07, 04:37 PM
I never really understood why systems separate attack and defense anyway. If I learn to use a weapon, I learn how to attack *and* how to defend with it. When two people are fighting, both are constantly trying to attack (unless one has a really good reason not to).

Same reason why most systems separate attack and damage (some don't, like Fate or nWoD) - because it adds variety. That way you can have offense-oriented glass cannons, defense-oriented tanks, characters who hit infrequently but pack a punch, fragile speedsters, and all other kinds of combat styles. Replacing it all with a single Combat stat might be more streamlined, but it's also less interesting.

warty goblin
2013-09-07, 10:13 PM
Same reason why most systems separate attack and damage (some don't, like Fate or nWoD) - because it adds variety. That way you can have offense-oriented glass cannons, defense-oriented tanks, characters who hit infrequently but pack a punch, fragile speedsters, and all other kinds of combat styles. Replacing it all with a single Combat stat might be more streamlined, but it's also less interesting.

It seems like you could get a lot of that variety with options and effects that modified what the combat roll does. After all, many blows delivered in actual weapon combat don't hit, but are important because they set up the next blow. And there's a lot of variety in how a person can set up that next blow. This is particularly true of something like sword and shield combat, where actually landing a hit against somebody can be a fairly protracted process. Besides which, a lot of the classical variety is frankly kinda boring.

Iloveweb
2013-09-09, 07:16 AM
Tenra Bansho Zero simply lets a successful melee defense roll count as an automatic counterattack. So if you beat your opponent's roll, you deal damage instead of them.

I love Tenra Bansho Zero , it's awesome game .

Autolykos
2013-09-09, 07:41 AM
Same reason why most systems separate attack and damage (some don't, like Fate or nWoD) - because it adds variety. That way you can have offense-oriented glass cannons, defense-oriented tanks, characters who hit infrequently but pack a punch, fragile speedsters, and all other kinds of combat styles. Replacing it all with a single Combat stat might be more streamlined, but it's also less interesting.You can still do that to an extent, just by choosing different equipment (and learning how to use it). Wearing armor makes you more defensive, but slower. Using a shield is more defensive, TWF gives more chances to hit, two-handed has more reach and damage. This also gives fighters more flexibility. They aren't limited to one role by their "build", they can adapt their equipment to the mission and perform well in different positions.
And then there's techniques that can be more useful for offense or for defense, even without having two clearly separated rolls to which they could add a bonus or penalty. It may require more thought to design, but I find the result to feel more plausible.

Erasmas
2013-09-09, 11:49 AM
I think I have a base idea to work from with this. What I have basically boiled it down to is:

Each round, everyone involved in the combat secretly writes down three actions for that round - chosen from Attack, Defend, and Move. You then roll for initiative resolution at that point (it could either be per round, or you could do it per action if you wanted) and begin working your way through in order. If someone Attacks you with their first action and you had decided on Defend as your first action, then you roll normally. If you didn't have a Defend action chosen until your second or third action, then you can forfeit your prior actions for a "hasty" Defend action (probably at some kind of minus). And so on.

So, one could decide to take Attack, Move, Attack for this round and then choose Defend, Defend, Defend the next. The differing elements could get bonuses/penalties to certain actions and whatnot. Obviously, you could add a whole mess of addendums and things that bend the rules if you have a particular feat/training/skill/whatever to mix it up.

Thoughts?