Knockback

[afnord]

As I see it the knockback rules represent somebody losing their balance and stumbling backwards from the force of a blow.

IIRC in Gurps there is no knockback from bullets or arrows....ever. It only applies to melee and hand to hand. Also knockback from impaling and cutting weapons only applies if the blow fails to pierce armor else the kinetic energy is spent making a hole or a cut. So that leaves crushing weapons and cut/imp that fail to go through armour.

Knockback does not mean that you fly through the air, only that you stumble back 1 yard per 8 in BASE damage (ST10), if you are applying cutting or impaling bonuses then no knockback should have occured in the first place.
If you fail DX then you fall backwards.

Me with a Karate running jump kick have managed to kick a person 3 yards backwards. The person was holding a pad and bracing for the kick....the difference was that I weigh 250 lbs and the person holding the pad was a 140 lbs woman. The person did not fly backwards but lost her balance, stumble backwards and fell.

Also you should try to find a person of equal weigh and push with all your body behind the push. I did this once to a guy who was trying to pick a fight and he was not ready and stumbled 2 yards backwards before falling on his ass.

[Tomsdad]

Originally Posted by Skarg

More examples of falling down from real life. Look at the starting position, and whether the target ends up in their own hex or not. I'd call these fallback rather than knockback, because it's not like the force of the blow is making them fall back. It's more like people falling down very frequently end up 1-2 yards away from where they started falling down, just as part of losing balance. Falling in your own hex and an adjacent hex, as GURPS has as the non-knockback result, seems to look less natural.

Sitting target punched for knockdown and 1-hex fallback:
http://i.imgur.com/5x2ROHB.gif

Standing target hit with thrown basketball for knockdown and 1-2 hexes fallback:
http://i.imgur.com/nSCjsv9.webm

Standing target hit with thrown soccer ball for knockdown and 1 hex fallback:
http://i.imgur.com/PpEkFH6.webm

No hit; 2-hex simple trip & fall:
http://i.imgur.com/Q3ow3an.gif

Hmm I think I'd call the first three all knocked down into own hex* and adjacent hex actually (also demonstrating why face get knockdown check at any injury).

The thing is there is some rolling around afterwards that probably end up in other hexes. In GURPS terms on a 1 second turn basis I'd say that's moving while being prone.


Sorry I couldn't get the last one to go for me,


*the sitting chap can't get knocked directly down as there is a chair in the way

[Rupert]

Originally Posted by Anthony

Being able to push people around is useful, but it's neither realistic nor particularly in genre outside of being batted around by giant monsters.

I think it's useful and in genre, if not entirely realistic, in my Traveller game, seeing as the most common knockback in it is from explosives. It is also useful as throwing characters around, knocking them over, and blowing their equipment off them inconveniences them even when they're in very heavy armour. It can also cause falling damage, which unlike most other forms of damage causes blunt trauma through rigid armour.

There's also the humour factor "Hey, Happy, that's a new flight record!"

[Skarg]

Originally Posted by Tomsdad

The thing is there is some rolling around afterwards that probably end up in other hexes. In GURPS terms on a 1 second turn basis I'd say that's moving while being prone.

Ok but it's not voluntary movement, so how would you handle that?

We have played with house rules for prolonged falling/rolling/slipping/sliding (or "Tumbling"), but GM discretion is required. If you're knocked down, you may need to roll vs. DX (with modifiers including shock and stun) to avoid entering a Tumbling state, where you keep rolling away each turn until you make a roll or get someplace where the GM rules the terrain has you stop. It takes playtesting & tuning though to have it work out well and not seem weird or unbalanced. Of course, real mayhem is often weird, as seen in those videos. One of the trickier part for me is that the motion in video evidence is often based on weird body movements. Another is that it's also highly dependent on terrain specifics, which is hard to make general rules for, so it ends up being GM dependent.

Of course it's miles better than other games & GMs I've seen - cases (not in GURPS) where people's characters died out of combat by slipping and rolling down a hill mainly due to improvised game mechanics.

Here's a funny flying kick knockback that the comment above reminded me of:
http://i.imgur.com/HaKAyI0.webm

And everyone's favorite, the critical failure kick that results in self-knockback:
http://i.imgur.com/2gcnK5H.gif

Cow kick knockback:
http://i.imgur.com/aM6MuAz.webm

[Tomsdad]

Originally Posted by Skarg

Ok but it's not voluntary movement, so how would you handle that?

TBH looking again at the one's that show for me I'd say its all pretty much part of the initial falling down and pretty much stays within what in GURPS would roughly be a hex. So I wouldn't need extra rules for it.

The thing is while combat in GURPS precisely defines a hex, real life doesn't so I wouldn't go looking for exact match ups.

Originally Posted by Skarg

We have played with house rules for prolonged falling/rolling/slipping/sliding (or "Tumbling"), but GM discretion is required. If you're knocked down, you may need to roll vs. DX (with modifiers including shock and stun) to avoid entering a Tumbling state, where you keep rolling away each turn until you make a roll or get someplace where the GM rules the terrain has you stop. It takes playtesting & tuning though to have it work out well and not seem weird or unbalanced. Of course, real mayhem is often weird, as seen in those videos. One of the trickier part for me is that the motion in video evidence is often based on weird body movements. Another is that it's also highly dependent on terrain specifics, which is hard to make general rules for, so it ends up being GM dependent.

Of course it's miles better than other games & GMs I've seen - cases (not in GURPS) where people's characters died out of combat by slipping and rolling down a hill mainly due to improvised game mechanics.

Again unless you fighting on a really extreme surface I wouldn't bother with anything like that. I certainly think the videos you posted are supported by the knock-down, stun, footing rules and getting back up rules as is.

Originally Posted by Skarg

Here's a funny flying kick knockback that the comment above reminded me of:
http://i.imgur.com/HaKAyI0.webm

And everyone's favorite, the critical failure kick that results in self-knockback:
http://i.imgur.com/2gcnK5H.gif

Cow kick knockback:
http://i.imgur.com/aM6MuAz.webm

Now the 1st and 3rd are definitely knock backs as per the rules, but the first is an all out attack flying kick (and to be fair to him he gets the distance just right and hits with plenty of forward momentum to spare*). The third is a cow.


*in fact even though GURPS separates such things, I'd argue in terms of knock back that's as much a flying slam as a kick!