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DMMike
01-03-2009, 10:32 AM
I've been trying to use defense rolls to keep players involved outside of their turns:

"The ravenous bugblatter beast of Traal engages you, make five defense rolls."

The mechanics I'm using:
NPCs have an Attack Class (AK) against which PCs must roll a D20 and add their defense scores.
A defense score is an AC less 10.
An AK is 12+ the character's attack bonus.
When a defense roll equals an attack class, the attack misses.

The main thing I haven't resolved is how to use this in NPC-only conflicts, because I there's no roll to make two Classes compete; they're static.

Any opinions? I could automatically subtract 10 from the AC and roll on that (and get confused when the two scores equal each other)...or make a judgement based on the difference between the two scores. Or...

Webhead
01-03-2009, 10:49 AM
I hope you brought a towel.

Sorry. ;)

I'll have to do some head scratching on this one.

tesral
01-03-2009, 07:34 PM
More scratching from over here.

TAROT
01-03-2009, 09:08 PM
I'm not exactly sure what you are doing here.

The base d20 system assumes that everyone is taking 10 for defense. So a defence roll becomes AC-10+d20.

If you want to implement defence rolls for players, usually you would have the monsters take 10 on all attack rolls. By adding a defence roll, the GM should be hardly touching the dice. (Except for damage, and even for that, you could always assume average.)

And if you want to have NPCs go at it, just make something up and get back to the important characters (i.e. PCs). Don't make the players watch you roll a bunch of dice that doesn't involve them.

Malruhn
01-03-2009, 10:30 PM
You just took the passive role of Armor Class and turned it into an unnecessarily complex active action.

Do you make your characters roll to breathe as well?

(You're gonna need that towel!)

DMMike
01-04-2009, 11:07 AM
I wouldn't call avoiding bodily injury a passive action!

I'm with you on making up NPC fights, Tarot. The twist is that NPCs and PCs can fight at the same time, like with henchmen or summoned creatures. I'm thinking that a quick comparison of the AK versus AC will provide a shorthand for how often one hits (if avoiding a normal D20 roll is necessary). Each point that an AK is above an AC is 5% better odds that an attack will hit. If I did my D&D math right, the attacker's DC is 11 minus the difference in the scores. So an AK 17 versus an AC 15 needs a 9 or better to hit.

And an example of defense rolls in action, in case there was some confusion:
DM: The fiendish mother-in-law:mad: attacks. Make a defense roll.
Player: (adds defense bonus to a D20) 19! Yes!
DM: (notes FMIL's attack class of 29) The fiendish mother-in-law cackles at your feeble attempt to block her slap, and the impact nearly knocks you to the ground...

tesral
01-04-2009, 11:34 AM
I wouldn't call avoiding bodily injury a passive action!

And an example of defense rolls in action, in case there was some confusion:
DM: The fiendish mother-in-law:mad: attacks. Make a defense roll.
Player: (adds defense bonus to a D20) 19! Yes!
DM: (notes FMIL's attack class of 29) The fiendish mother-in-law cackles at your feeble attempt to block her slap, and the impact nearly knocks you to the ground...

However that isn't a mechanic in D&D attack/defense is not an opposed check. I see no reason to make it one just so more dice get rolled. Yes, defense is not passive, but your ability to defend actively is represented by the Dex bonus in your AC.

You could do this, but I don't see a reason to do so. It has always been assumed that combat happens all at once. We divide it into turns to make it possible to work out what is happening in an orderly fashion.

TAROT
01-04-2009, 07:53 PM
However that isn't a mechanic in D&D attack/defense is not an opposed check. I see no reason to make it one just so more dice get rolled. Yes, defense is not passive, but your ability to defend actively is represented by the Dex bonus in your AC.

It's not more dice, it's just changing who rolls them.

First level fighter. Attack +4 (+1 BAB, +3 Str) longsword 1d8+3. Defence +6 (+5 chain, +1 Dex)
Gnoll. Attack 13 battleaxe 1d8+2. AC 17.

Fighter attacks gnoll. Player rolls d20+4 vs 17.
Gnoll attacks fighter. Player rolls d20+6 vs 13.

Thinking more on NPC vs NPC stuff, you could apply the attack/defence difference as a bonus/penalty to damage.

DMMike
01-04-2009, 08:12 PM
I'm thinking the simplest way for NPC attacks is just to drop 10 off the AC and make a defense roll, and use the attacker's AK. That way, I don't have to worry about whether an AK/AC difference is positive or negative.

By the way, I'd like to rephrase the monster's name: Mother In Law, Fiendish. Now you can use the acronym without feeling like a pop culture tool.

tesral
01-04-2009, 10:53 PM
OK, I get the idea, but I'm failing to see the play benefit here. Why use a different mechanic for the players and the NPCs? Just so the players roll more dice?

If your players are getting bored while the GM rolls a few dice, like Mantis they need to learn Patience, and/or develop an attention space longer than five seconds.

TAROT
01-05-2009, 02:02 PM
Swapping the position of one d20 roll and one Take 10 isn't a different mechanic, it is a very minor change in the default implementation of the existing one. (And it's also an option on p64 of the 3.0 DMG.)

For me, the benefit is not so much that the players roll more dice, but as GM that I roll less (or no) dice. I'd rather just concentrate on dialogue, description, my notes and the story. Unisystem and M&M are especially friendly to the "GM never touches the dice" mode of play but d20 is okay.

It keeps the players more involved. Whether they are acting or reacting, they're the ones rolling the dice, and, in general it ups the stress level a bit to leave their fate in their own hands (especially if they're superstitious about their dice).

It provides transparency and removes a lot of potential GM fudging. Some groups like to let the dice fall where they may, and it's easier to just let the players roll the dice in the open than to fling them over the screen and retrieve them.

Also, it speeds up large combats against groups. If ten orc archers pop out of the bushes. It's much, much faster to have each player make two defense rolls against a fixed attack value, than for one GM make five sets of two attacks against five different ACs.

ignimbrite
01-05-2009, 02:46 PM
I've been trying to use defense rolls to keep players involved outside of their turns:

"The ravenous bugblatter beast of Traal engages you, make five defense rolls."

The mechanics I'm using:
NPCs have an Attack Class (AK) against which PCs must roll a D20 and add their defense scores.
A defense score is an AC less 10.
An AK is 12+ the character's attack bonus.
When a defense roll equals an attack class, the attack misses.

The main thing I haven't resolved is how to use this in NPC-only conflicts, because I there's no roll to make two Classes compete; they're static.

Any opinions? I could automatically subtract 10 from the AC and roll on that (and get confused when the two scores equal each other)...or make a judgement based on the difference between the two scores. Or...

So you are describing the system from Unearthed Arcana page 133?
Attack Score: 11 + enemy's attack bonus
Defense Check: 1d20 + character's AC modifiers

Anyway why stress about NPC vs NPC combat - use the system above. It just means that there will be no rolling and you easily know who is going to win the combat.
OR just make it up and have the combat be plot driven and not mechanics driven.

Etarnon
01-06-2009, 01:26 AM
I've done it the standard way and the reverse attack way.

some players like it, others loathe it, especially when they crit themselves by attacking as orc # 3.

Much better to hate the GM and the dice, rather than themselves for muffing the roll.

..on them superstitious players, that is.

We did this with 1e, even.

The orc needs a 19 to hit you, you just don't want to roll a 19 or *gads* 20.

interesting to see this pop up here.

DMMike
01-06-2009, 08:32 AM
Et - good point about putting things in perspective. The simplest way to do a defense roll is simply to ask the PC to make the enemy's attack roll. What I love, is that while an Enemy Attack Roll and a Defense Roll accomplish exactly the same mechanic, they inspire completely different mind sets. The EAR is the DM's fault; the DR is the player's fault.

"I made the orc hit me." - "I didn't avoid the attack well enough."

It's important to try and minimize player-bitterness, but you bring up another important point: the physical aspects of the DM roll. If the DM rolls behind the screen, he can fudge a roll. If he rolls in the open, like a defense roll by the player, he can't.

But I still like the defense roll, because the DM can still fudge the damage :)

Etarnon
01-06-2009, 08:56 AM
I roll everything for combat in the open, hits, damage, etc. Clean rolls on the table.

That way, it is what it is, the dice don't lie. NPCs got it, they did. Pcs got it, they did. that way you can clearly assess your risk, and go for it, and hope the enemy doesn't hit or crit, but if so, you had the chance to run.

Makes for lots of drama, since there is no "God behind the screen" to appeal to. You trust your clerics / medics / cyberdocs to get to you in time.. but sometimes they don't.

Secret doors and such or info rolls, I do behind a screen.

1958Fury
01-06-2009, 10:58 AM
I could see a point to it. Does my standard AC include any blocking I might do? It must, since it includes my shield. So why would my AC be the same every round? Some rounds I'm going to be in a better position to block than others.

So, if my normal AC is 20, and my shield is 5 of that 20, perhaps I could roll each round to see if I get to add that 5 to my AC. If I fail my shield roll, then my enemy only has to beat AC 15 to hit me. (...and similar applications for other forms of blocking & dodging, etc.)

It might make for some more exciting fights, and could be good for a PvP battle. But I don't think I'd personally use such a system. PnP battles have plenty of dice rolls already, and I'd rather see things get less complicated, not more.

Webhead
01-06-2009, 11:00 AM
I think I get it now. Attack as a set value and Defense as a roll to contest (right?).

If you want to minimalize DM dice rolling and put more of it in the players' hands, I would suggest taking a page from Cinematic Unisystem's suggestion for handling NPCs:

Give NPCs set values or DCs for both their attack rating and their defense rating (i.e. [Evil Monster X] has an Attack Class of 20 and an Armor Class of 18). What this does for gameplay is have your PCs roll to defend themselves against the monster when it attacks, but still roll to hit the monster when it is their turn. The DM has almost no rolling to do in combat and can instead focus on describing the opponents' actions and the PCs feel more personally accountable for their combat performance. This keeps all calculations flowing in the same direction which can streamline the process. You also don't have to tell the players what the Attack or Defense classes are, just tell them whether they succeed or fail. (I've considered implementing this system before in d20...specifically M&M and I rather liked the idea.)

How to handle NPC versus NPC combats: just have an attacked NPC make a defense roll as if it were a PC (rolling Armor Class -10 as normal) against the attacking NPC's Attack Class

OR

Simply compare the attacker's Attack Class against the defender's Armor Class if desired. This has obvious implications within the context of D&D (i.e. guaranteed hit/miss) but decide for yourself if that is important to the way your NPC vs. NPC contests will play out.

Some suggestions.