Knockback rules

[Kershek]

Looking for comments. Is this viable in the game? It is not a feat or a special ability; it just happens if the attacker wishes it. It's to simulate the "Sauron" effect when large, powerful creatures attack smaller ones. It has not yet been playtested. Thanks!

Knockback
Knockback occurs on the attacker's option when a creature is dealt enough damage. The more damage, the further a creature gets knocked back and the more chance he will be sent prone afterwards. A larger creature hitting a smaller creature can cause knockback easier. Knockback can only occur if the opponent is the same size or smaller than the creature doing damage. The creature determines if knockback is activated before they roll damage.

A creature can cause a similar-sized opponent to be knocked back 5 feet by dealing 40 points of damage in one blow. For each size category larger is the attacker, the blow required for knockback is half as much. Therefore, a large attacker only needs to do 20 damage to a medium-sized opponent to do 5 feet of knockback. Please see the following chart for knockback requirements:

Attacker       Damage required
---------      ---------------
same size        40
+1 size          20
+2 size          10
+3 or more size   5

Knockback distance is increased by 5 feet for each doubling of damage required. Therefore, a huge creature that does 30 points of damage to a medium-sized opponent sends him flying back 15 feet.

Landing prone: When a character is knocked back 5 feet, they must make a reflex save of DC 10 to stay on their feet or be knocked prone. For every 5 feet futher they are knocked back, the DC increases by 5. A creature with the tumble skill can substitute their tumble roll in places of a reflex check if they choose.

Knocked back     Reflex save or prone
------------     --------------------
5  feet            10
10 feet            15
15 feet            20
20 feet            25
25 feet            30
30 feet            35
35 feet            40
40 feet            45

Knockback into a wall: If a player is knocked back into a wall, they take 1d6 points of non-lethal damage per 5 feet of total knockback distance whether or not they actually traveled that distance before hitting the wall. For instance, a creature is given 20 feet of knockback, but there is a wall 10 feet back. They will take 4d6 points of non-lethal damage when hitting the wall even though they didn't travel the full 20 feet. This simulates the possibility of being knocked out by the force of impact. The possibility of landing prone is unchanged.

Knocked back     non-lethal damage
------------     --------------------
5  feet            1d6
10 feet            2d6
15 feet            3d6
20 feet            4d6
25 feet            5d6
30 feet            6d6
35 feet            7d6
40 feet            8d6

 

[AeroDm]

All in all I'd say it looks fairly well put together. You must realize that you are adding in a rule that empowers larger creatures without any hindrance, but I have always enjoyed the flavor of such things so it doesn't bother me.

A few things I'd note, on the reflex saves I'd format it differently to be distance traveled +5 for the dc. Works out exactly the same but is easier to do in your head for some reason.

Additionally, I'd change the non-lethal damage to 1d6/10' instead of /5' just to keep in line with the falling rules. Also, the character already took 40ish damage to be flying backwards anyhow, why add on another 4d6 non-lethal? I'd probably let people use the tumble rules to negate 10' of this as well. You don't want to make this _too_ powerful of a flavor addition...

Good work, with a little fleshing out could be very cool.

 

[A'koss]

I'm looking to institute some kind of (simple) knockback rules for our campaign. Has anyone else taken a stab at this? I agree with AeroDm's comments here on your take on them - keep the damage consistant with the current rules and it'll be easier to remember.

 

[Kershek]

My original thought was to make it 1d4 per 5', but that didn't seem very significant considering the pounding you just took. Plus, the situation of having a wall in your path probably won't come up that much. Plus, by the time you meet a creature that can knock you back by 30' you can probably take the punishment of 6d6 non-lethal (average 18). If you can't, you just get knocked out.

I like the reflex save as DC = distance traveled +5. Another thought I had was a balance/tumble check DC = distance traveled instead of reflex save.

 

[Kershek]

On second thought, I agree with the 1d6 per 10', just to make it easier to remember with the falling rules. I also agree with the tumble to make it 10' less worth of non-lethal damage. Thanks for the comments.

 

[AeroDm]

I had a few more thoughts on the system that I figure'd I'd share with ya...

First is the fact that there should probably be some save (fort?) to negate the affects. It isn't really fare for the 20th level fighter to be tossed around like a rag doll from 40 damage when he has 200+ hps and views that 40 as children's play. Not sure what I'd do for numbers on this...

Alternatively, I'd consider not having any save but then making this a feat. If I took this approach, I'd probably add on the damage for distance regardless of whether or not they hit a wall. If you fly 20', you take 2d6. If a wall stops you 10' into it, you still take 2d6.

The expenditure of a feat makes it seem a bit more palatable to me.

 

[Wolffenjugend]

I think there's a feat covering this very topic in the 3.5 MM.

 

[Kershek]

Yes, it's called Awesome Blow but it has too many prerequisites, is too weak, and doesn't really have the flavor I'm looking for.

 

[Shadeus]

Just to play devil's advocate, what if a human fighter was attacking a collosal dragon? Said fighter charges up to the dragon and gets his one attack. Now the dragon bites him for 40 points of damage (which is by no means the maximum, or even a critical), that means the fighter is forced back 40' and then has to make a DC 45 Refl save or land prone. That doesn't seem way overpowered? The dragon would be flicking off adventurers over cliffs like it was a sport!

The dragon was just an example of a very large creature. There's lots of other examples. Because of the level at which you reduce the damage for each size category, it only makes it easier for big creatures who have a greater potential to do more and more damage to knock characters back.

I think this will lead to very frustrated melee characters who won't have the good Reflex saves to begin with and will like spend most of their time getting on their feet and then approaching the monster only to have them knocked back again.

With the knock prone feature, it is a much easier method to trip characters. So a high strength fighter has no chance against this. You might be better off re-working this to work similar to a bull rush.

It looks a bit overpowered in my opinion. But if it suits your campaign, good luck!

 

[AeroDm]

I agree that it is really powerful... but the flavor is really cool. I think the mechanic breaks down when you start getting into higher levels because it is based on static damage numbers while damage actually diminishes. At lower levels, the 40 dmg needed to toss you back basically kills you, so landing prone is just style. At higher levels that same 40 damage is nothing, so this becomes a game breaker.