unstable terrain: how does it work?

[whswhs]

The Basic Set definition of Terrain Adaptation refers to "the DX and Move penalties that most characters experience on that terrain type." But I'm not sure what those penalties are!

Martial Arts refers to -2 to attack and -1 to defend for bad footing. But you can buy that off with a 1-point perk, Sure-Footed. If that's all that's involved, then buying Terrain Adaptation for 5 points is just crazy; there's no reason anyone would ever do it.

I'm wondering, in particular, if trying to move at full speed on unstable terrain would count as "pushing the envelope," with a risk of losing traction and falling, as if, perhaps, you had failed a Skating roll.

Has this been established anywhere in the published rules? Or if not, what seems like a reasonable extrapolation from those rules?

[Rolando]

Terrain adaptation is more than training to combat in slippery floor, wich may be the perk.

It is also generic, it will help with terrain like soft sand, swamp, deep snow, etc. Terrain that convey penalties to movement and combat. Each instance of terrain adaptation help with a particular type of terrain.

It still may seems as too costly if difficult terrain is not common in the campaign and it is more like a racial feature, but it will depend a lot on the campaign and GM if the particular terrain comes into play or not.

If it is uncommon in a campaign I can see a GM allowing the advantage for only 1 point... but that is a GM call.

Edit: In GURPS Basic: Campaigns, pg.351, there is also the Hiking rules, Terrain Adaptation will also help with those. Soft sand, swamp and deep snow are movement x 0.2; also in pg.387 there are some "bad footing" modifiers, mostly 1/2 speed, but a GM may rule it as worst (1/5 speed); and of course the Bad Footing attack modifier -2 or more.

[Ulzgoroth]

I'm pretty sure Basic mentions increase movement cost to enter(?) bad terrain hexes. I'm on a new computer and don't have books at my fingertips yet to pull a citation.

[whswhs]

Originally Posted by Ulzgoroth

I'm pretty sure Basic mentions increase movement cost to enter(?) bad terrain hexes. I'm on a new computer and don't have books at my fingertips yet to pull a citation.

The Move penalties seem fairly straightforward. But I'm not seeing the DX penalties. Can anyone provide a page citation?

And, well, if I step onto an icy surface, I'm at risk of slipping (that happened to me a couple of times during my first Kansas winter!) and perhaps of falling on my butt. Are there any rules that cover this? The existence of Perfect Balance suggests that it's something that needs to be protected against, but what roll does that protection modify?

[Rolando]

I see no DX penalties beyond Bad Footing (-2).

I think it is something the GM decides when to roll and at what penalty if any.

In GURPS Russia (3ed) there are more detailed rules for snow and ice, movement and actions/combat. Page 30 and 31.

Not to copy all the rules here but mostly DX -2 to not fall when entering ice and DX-2 to stand up again, this for very slippery ice, rouged up ice may be easierm even no DX roll if moving very slowly.

For combat it is also mostly the -2 penalty and some other details, also that the attacker may ignore the penalty but then must roll DX-4 to not fall.

So the Bad Footing modifier in Basic is the way to go with added detail as needed or desired.

There are a few other rules and details, specially for overland deep snow movement, it is a great book so it is good investment if you want the extra detail, but probably @whswhs you already have it.

Edit: In GURPS Magic (4ed this time) there are lots of more detailed modifiers in the Grease Spell (pg. 142) and Ice Slick (pg.186), bot are very similar but not exactly the same, probably another GURPS Magic inconsistency but mostly -2 to -3 mods and a chance of fall.

For soft sand and swamps the Bad Footing modifier may be less and maybe no chance of a fall. For other difficult terrains (like loose gravel o other rough terrain) maybe there is no Bad Footing mod, only a movement penalty.

[whswhs]

What is the page number for Bad Footing? And in particular, what is that for "roll DX-4 to not fall"?

[Rolando]

Bad Footing is in the combat modifiers, in page 547 (melee attack, attacker situation -2 or more), 548 (ranged attack, attacker situation -2 or more) and 549 (defense, defender situation -1 or more).

The -4 DX to not fall if ignoring the "bad footing" modifier is an addition in the GURPS Russia (3ed), same page as the rest of the Ice rules (pg. 31)

[whswhs]

Originally Posted by Rolando

Bad Footing is in the combat modifiers, in page 547 (melee attack, attacker situation -2 or more), 548 (ranged attack, attacker situation -2 or more) and 549 (defense, defender situation -1 or more).

The -4 DX to not fall if ignoring the "bad footing" modifier is an addition in the GURPS Russia (3ed), same page as the rest of the Ice rules (pg. 31)

Okay, thanks!

Unfortunately, I thinned my gaming library on a previous move, and I no longer have GURPS Russia. I'm not sure what it means to "ignore" bad footing. Does this mean that you're moving faster than the reduced speed for the bad footing modifier? That would kind of make sense.

What I'm looking at, though, is heavy rain on a paved road. The Basic Set says you treat this as average terrain, which gives you 100% of movement speed, so it would seem that you can move at full speed with no risk of falling. And yet I HAVE slipped on wet pavement. And wet pavement at least imposes penalties to attack and defense, because a slippery surface is one of the things Sure-Footed can counter . . .

Please don't feel that I don't appreciate your help. Your answers are actually quite useful! I'm just trying to pin down something that the rules may not fully address.

[Rolando]

No worries, I just don't want to put all the rules here, I think it is not a good practice.

Yes, the "ignore penalties" part is that if the character don't want to receive the Bad footing penalties they must succeed in a DX-4 roll or fall.

I think the key point is that it is a GM call, and -2 to actions and -1 to defenses as a base, average or generic bad footing (due to slippery, unstable or uneven floor I may add).

I think that with good shoes in an average (somewhat clean) concrete floor or pavement there is almost no risk of falling, if the concrete have mold or grease then water makes it a lot more slippery.

With shoes that are not designed to doing activities in wet floors (most dress shoes) i think there may be additional penalties. With shoes designed specifically for wet floors (most rubber boots, specially those for working in cold storage rooms, kitchens, etc.) there may be some bonus to any rolls to prevent a fall.

Also remember, paved roads are made to be not slippery during heavy rain, so as long as the characters have good outdoor shoes (specially motorcycle riding boots, outdoor boots, combat boots for example) it is improbable that they will need a roll at all, and at least the penalties should be reduced, maybe the result of a critical failure is a skid and a DX or Acrobatics roll to prevent a fall.

The slipperiest ice is -2, grease (as in the Grease spell) is also -2.

[whswhs]

Originally Posted by Rolando

Yes, the "ignore penalties" part is that if the character don't want to receive the Bad footing penalties they must succeed in a DX-4 roll or fall.

So you have two choices: suffer bad footing penalties, or risk a fall, which it takes a DX-4 roll to avoid.

Bad footing gives you -2 to attack rolls, and -1 to DX rolls. I'm not sure what you can be doing that simply negates those penalties.

I can see that if bad footing reduces your movement speed (something that doesn't seem to be spelled out very explicitly in the published rules), then you could say, "Never mind the risks, I'm going to move at full speed!" And then you either get there or fall. I suppose you might say that having to move slowly and carefully hinders your attempts to attack and defend, and that you might (a) get out of the way of an attack but (b) fall down, for example, if you move fast; is that what you think is going on?

There's also mention of DX penalties as a broader category. I'm not sure what is being penalized there. I presume it hinders DX rolls if you're called on to make one. I don't suppose it hinders the DX-4 roll to avoid falling; you've already got a -4 penalty, and applying an extra penalty would seem harsh! Does it apply to DX-based skill rolls, do you think, or some of them? (I can see that Dancing would be a problem. I don't this I see Sewing. It almost seems as if having to move slowly and carefully would be a PLUS for Stealth . . .)

If you have Perfect Balance, you get +6 to keep your feet. Does that cancel against the -4 to let you roll vs. DX+2 to move quickly?

What do you think?