Environmental Objects (3.5e Variant Rule)
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 Environmental Objects
There are times in your campaign where you wish to use the environment to further your needs. Making good use of your environment is a step that can be taken in order to increase your chances to get out of an encounter alive. Using your environment can make the difference between being stamped by insurmountable odds and a glorious victory bought with great hardship.
Did you ever see one of those old swashbuckling movies, like The Count of Monte Cristo, or a movie featuring Jackie Chan? Then you know what can happen if you use your environment to aid you in your battles. Furthermore, it can make an otherwise boring fight scene of repeated generic attacking and being attacked quite a lot more bearable. For added kick, try to mimic some of the sound that an object makes when it suddenly falls on top of the party's tanker, and the subsequent shrieks of the party wizard that momentarily lost his meatshield.
 Interaction with Objects
To an average taverngoer, who steps into the pub for a good old pint, a table is just that. A table. Usually, quite very much an object that is rooted in place. The rougher elements however might have a completely different idea about the functionality of such a basic object.
 Flip, Topple, Dislodge
Meet Bob. Bob is the local roughhouser. He goes to a pub to mess it all up. He gets drunk like a demon, screams from one side of the pub to the other, socks your mother-in-law in her face and takes a crap in the kitchen pantry the size of a birthday cake. Bob finds all kinds of different objects that he can use as improvised death machines. An ordinary tankard can become a light improvised weapon doing 1d4 base damage. A chair can be lifted and decked over a person's head (let's say a two-handed improvised weapon, 1d10 base damage). Certain objects are too big to use as weapons in a conventional sense, but they're not too big to influence.
Flip: Flip considers objects that can be lifted up and flipped about. Objects that belong to this class are medium sized furniture like a park bench or that sturdy oaken table from before. Flipping actually involves a bit of lifting before said object can be decked down on top of some insolent bar patron. Because of this, flipping is somewhat more difficult based on the weight of the object than pushing. To see if a certain object is fit for flipping, try to think of it as a point mass, before looking at its shape. Is its center of gravity low down? Does it have a broad base that isn't easily pushed over? In that case, it's likely a flippable object. Flipping an object requires a Strength check with a DC of 1 for every 10 lb. that the object weighs. An average table, then, weighing in at about 100 lb. will require a DC 10 Strength check to flip.
Topple: When you put your shoulder to a large bookcase, in order to push it over, that can be considered toppling. This category is filled by all manner of furniture that is built up against walls. You can push an archive bookcase on top of an unsuspecting zombie, or put your hand behind a wall mounted bookcase and pull it down on top of the blackguard that is hot on your heels. If the object you are thinking off has a shallow base, like the narrow girth of a bookcase, it is perfect for toppling. Toppling an object requires a Strength check with a DC of 1 for every 25 lb. that the object weighs. A fully loaded bookcase taking in 5 feet of wall will quickly weigh 500 lb. Pushing that over with a DC 20 Strength check shouldn't be a problem for real tough bastards.
Dislodge: Certain conveniently placed improvised weapons tend to be affixed to certain things, like a wall-mounted chandelier or a metal bar-rail. In the hands of a somewhat creative brawler, these weapons are quite deadly. The DC for prying loose objects may vary, but a DC of 10 or 15 for a chandelier and a DC of 20 for a bar mounted rail for instance would work quite well.
 Size and Strength
Strength of course is measured in no small part by size. If you're really big, it's easier to push things over on no small account due to your own considerable weight. Flipping and Toppling, as described above, should be considered as no more than an application of carrying capacity, and said carrying capacity differs by size. A Large creature with a Strength score of 15 can carry twice as much as a Medium creature with a Strength score of 15, who can again carry twice as much as a Small creature with a Strength score o 15. Logic would dictate that for Small creatures, Flipping and Toppling DCs should be doubled, and for Large creatures, they should be halved. For the Large creature, pushing over that overflowing 500 lb. bookcase would be a DC 10 piece of cake instead of a DC 20 episode of gruel and sweat, since he himself likely weighs 500 lb. or more himself. For a Small creature, it is likely quite impossible at DC 40. Ever seen a pixie fell a tree?
 Object Weight
If you're going to give the players the option to use objects in this way (I think you should, since tabletop DnD is one of the most customizable form of roleplaying there is), then it is smart to agree on a set weight, like so.
|Object||Suggested Weight (lb.)||Suggested Action||Suggested Hit Points||Damage|
|Bed (fourposter)||500||Flip / Topple||50||5d6|
|Dresser (empty)||75||Flip / Topple||12||1d6|
|Dresser (full)||150||Flip / Topple||12||1d6|
|Table (sturdy oaken)||200||Flip||37||2d6|
Bear in mind that these figures roughly translate to Medium objects. A table in a Hill Giant's household, should it feel it has need of one, may likely be twice as heavy.
 Object Hit Points
A possible rule of thumb for object hit points can be derived as a function of their hardness and their size as the following;
Object Hit Points = sturdiness modifier × size modifier × (object hardness)²
with the size modifiers Tiny ¼, Small ½,, Medium 1, Large 2, Huge 4, Gargantuan 8 and Colossal 16
and sturdiness modifiers Flimsy ½, Average 1, Sturdy 1½ and Masterwork 2.
 Object Damage
The damage an object deals when keeling over on top of a medium creature is 1d6 damage per 100 lb. of the object's weight, rounded to the nearest number divisible by 100 (round down at a remainder of 50 or below) plus, if applicable, the Strength modifier of the creature that flipped or toppled the object on top of it. Minimum weight of an object so usable is 50 pounds, with a minimum of 1d6 damage.
Creatures should be able to make a DC 15 Reflex save to avoid damage.