Unusual Combat Situations (DMG)

Although most adventurers spend most of their time on foot, and on good old solid land where common sense and the normal combat rules can be applied, the player characters are operating in a fantasy world.
Sooner or later, player characters are going to lay siege to a castle, or leap on their horses, or learn how to ride an exotic flying creature. Eventually, they're going to pick up and go adventuring in some totally weird environment where the normal laws of physics just don't apply. Here, you'll find rules and guidelines for some ordinary, and not so ordinary combat situations.
== Siege Damage ==
The players will often encounter situations in which it is important that a stronghold be broken into. In these situations, the overall employment of siege tactics should be secondary to the thrill and glory of the players going "mano-a-mano" with their foes. In other words, the battle should be the background against which the players act. Sixteen months of siege may be realistic, but it isn't much fun!
The critical point in a siege is that moment when the walls face a direct assault. This is especially true in a role-playing adventure. The following table simplifies this process of breaking down walls.
To use the table, the DM determines what type of wall is being assaulted, and its closest approximation on the Table. Cross-reference the type of attack being made and roll 1D20. If the resulting roll is higher than the number required, the attack does no significant damage; if the roll is lower, the wall begins to give way.
For each point below the required saving throw, the structure loses one cubic foot of structure. For example, suppose a stone wall 10' thick fails its saving throw by six points. The wall now loses a portion of its structure equal to six cubic feet of area (i.e., a hole two feet wide, three feet high, and one foot deep).
 Table 52: Structural Saving Throws
 	————— Wall Type —————	————— Wall Type —————	————— Wall Type —————	————— Wall Type —————	————— Wall Type —————
Attack Form 	Hard Stone 	Soft Stone 	Earth 	Thin Wood 	Thick Wood
Ballista 	2 	3 	4 	10 	5
Giant fist 	3 	4 	7 	16 	9
Small catapult	4 	8 	5 	17 	9
Ram 	5 	9 	3 	20 	17
Screw or drill	12 	15 	16 	20 	12
Large catapult	8 	11 	10 	20 	13
== Mounted Combat ==
Fighting on horseback (or on a wyvern, unicorn, or pegasus, or whatever) is a different affair from battling on solid ground. The fighters must deal with their mounts—unpredictable and sometimes skittish creatures. Plus, the business of fighting on horseback demands different tactics from foot combat.
===Mounts—Trained and Untrained===
Mounts trained for combat (a heavy warhorse, for example) present few problems. These can be used in mounted combat with no penalties. However, steeds not trained for combat are easily frightened by the noise and confusion.
Those fighting from the back of untrained creatures suffer a -2 on their chance to hit, since much of their time is spent simply trying to keep the mount under control.
Panic: The rider of an untrained mount must make a Riding proficiency check whenever the mount is injured or startled by a surprising event (such as a lightning bolt spell blasting the rider or someone close by).
If the check fails, the mount panics and bolts, carrying its rider up to 1-1/2 times its normal move. Although the mount panics in a more or less random direction, it goes generally forward unless that carries it straight into the face of danger. If unable to flee, a panicked mount rears and bucks uncontrollably.
Characters without the Riding proficiency automatically lose control of a panicked mount. A proficient character can attempt to regain control once per round. Regardless of the rider's proficiency, the mount's panic lasts only 1d4 rounds.
===Fighting from Horseback===
In mounted fighting, a character gets a +1 bonus to his chance to hit creatures smaller than his mount. Thus, a man on horseback gains a +1 bonus to his attack rolls against all medium-sized creatures such as other men, but would not gain this bonus against another rider or a giant. Those on foot who fight against a mounted rider, have a -1 penalty; this not applied to attacks against the mount, however.
Lances are the preferred weapons of the mounted rider. However, the type of lance used (light, medium, or heavy) can't be greater than the size of the horse ridden (light, medium, or heavy).
Medium and heavy lances gain their striking power from the momentum of the mount. By themselves, these lances are not capable of doing significant damage. Simply stabbing someone with a heavy lance won't produce much in the way of results. Therefore, these weapons are most effective when there's plenty of attack space.
During the first round of a battle, a rider can attack with a heavy or medium lance. After this, however, the rider must break off (most likely by continuing past his opponent), turn his mount, and gallop back again. This series of actions takes one round. Thus, at best, a rider can attack with a lance once every other round.
If the rider wants to continue the fight close in, he must throw the lance to the ground and draw another weapon. Often, lances are used for the first attack and then discarded in favor of swords, maces, etc.
Another consideration to bear in mind when using a lance is that lances are breakable. Heavy and medium lances are relatively inflexible. The DM can make an Item Saving Throw (for crushing blow) on each successful hit. A light lance is made with a great deal of spring (bamboo or cane are common materials). An Item Saving Throw is made only if the number needed to hit is rolled exactly, after modifiers.
Missile fire from the back of a moving horse is possible only if the rider is proficient in horsemanship. Even then, only short bows, composite short bows, and light crossbows can be fired from horseback by normally proficient characters.
Long bows can be used by those with specialization (if this is used). Heavy crossbows can be fired once, but cannot be reloaded by a mounted man since the bracing and pull is inadequate.
If the mount is not moving, the rider can fire normally (with full ROF and chance to hit). When firing while on the move, the rider has his rate of fire reduced by one. A 2-shot-per-turn ROF becomes a 1 shot every two turns; and so on.
In addition, the distance moved modifies the attack rolls according to Table 53 .
 Table 53: Mounted Missile Fire
Mount's Current Movement 	Modifier
Not moving 	0
Less than 1/2 normal rate 	-1
1/2 to 3/4 normal rate 	-3
Greater than 3/4 normal rate	-5
===Being Dismounted===
The other great hazard and difficulty of mounted combatants is the risk of being abruptly and rather rudely dismounted. An opponent can make this happen in one of several ways.
Killing the Mount: This is the grim and efficient method. Once the horse (often an easier target) is dead, the rider is certainly dismounted. The steed automatically falls to the ground.
If the rider has the Riding proficiency, he can attempt to land safely on his feet on a successful check. Otherwise, the character also falls to the ground and suffers 1d3 points of damage. The character cannot take any action that round and must spend another entire round gathering himself back up and getting to his feet.
Lassoing the Rider: The more heroic method of dismounting someone is to try to bring down the rider without harming the mount. This is also more desirable from a bandit's point of view, as he would rather have a live horse than a dead one.
Certain weapons (such as the lasso) can be used to yank a rider off his speeding mount. However, riders with Riding proficiency can attempt to stop short, reining the horse in before the rope is fully played out. If the check is successful, the horse stops before the line goes taut. The rider remains mounted, albeit still lassoed.
Whether the proficiency check is made or missed, the person or monster wielding the lasso must make a Strength check with a +3 bonus for every size category he's bigger than the rider (or a -3 penalty for every size category smaller).
A 20 is always a failure and a 1 always succeeds—unless the DM deems the result utterly preposterous. If the check is successful, the roper remains standing and the rider falls. If the check fails, the fellow on the ground gets yanked down and possibly dragged along.
Weapon Impact: Riders also can be knocked off by solid blows from a variety of weapons. Any time a rider hits another mounted character or creature with a melee weapon 3' or longer and scores a natural 20 on the roll, the other character is knocked from the saddle, suffering 1d3 points of damage (if from the back of a normal horse).
Foot soldiers with weapons of 10' or greater have the same chance. Riders with Riding proficiency can attempt to retain their seating by rolling a successful proficiency check.
The Flying Tackle: Finally, those on horseback can attempt to dive on another rider by making an attack roll.
If the attack roll misses, the attacker falls to the ground, suffering 1d3 points of damage (more, at the DM's discretion, if the mount is larger than a horse).
If the attack roll succeeds, the target must roll a successful Dexterity check to remain in the saddle. If this roll succeeds, the rider remains mounted, but the attacker is hanging on his side, feet dangling just above the ground. If the attack succeeds and the Dexterity roll is failed, both the rider and the attacker fall to the ground.
Footsoldiers can also attempt to pull down a rider. This is handled by the rules for overbearing.
== Aerial Combat (Tournament) ==
On first examination, aerial combat seems just like normal ground combat. The only real difference is that the ground can be anywhere from 10 feet to 100 miles (or more!) below. This little difference, however, leads to a number of special problems and effects that never come into play during a ground battle.
The biggest difference is that everyone (except the rare creature able to hover) must keep moving forward. Stop flying and the result is a fall, often with disastrous results. Two flying creatures simply cannot face off in toe-to-toe combat.
Battles are fought in a series of passes, as each creature tries to swoop down on the other, attack, wheel, and return before the other can respond. Speed and maneuverability are even more important factors in an aerial battle than in an ordinary one.
Another big difference is that aerial battles are fought in three dimensions. While this is hardly surprising to creatures of the air, it often causes the plans and tactics of groundlings, accustomed to only two dimensions, to go awry.
In the air, attacks can come from ahead, alongside, above, behind, below, or any combination of these. A paladin riding a pegasus may find himself beset by harpies swooping from high and in front, low and to the right side, high and from the rear, and even straight down from above. Clearly, standard methods of defense and attack that work on the ground are going to do him little good here.
There are two ways of running aerial battles: the Tournament rules and the Optional rules. The Tournament rules can be used in any situation, but rely on the descriptions of the DM and the imaginations of the players for much of their effect. The Optional rules provide a more detailed system for fighting aerial battles with miniatures. The Tournament rules begin below.
==Maneuverability Classes==
How tightly a creature is able to turn is an important factor in aerial combat. To measure this, all flying creatures have a maneuverability class ranking from A to E (with A being the best). In general, creatures with a better maneuverability class can attack more often and more effectively.
Class A creatures have virtually total command over their movements in the air; it is their home. They can maneuver in the air with the same ease as a normal person on the ground, turning at will, stopping quickly, and hovering in place. For them, flying is the same as walking or running.
Class A creatures can face any given direction in a round, and are virtually impossible to outmaneuver in the air. Fighting in the air is no different from fighting on the ground for them, so they can attack every round. This class includes creatures from the elemental plane of Air and creatures able to fly magically, without wings.
Class B creatures are the most maneuverable of all winged creatures, although they lack the utter ease of movement of class A creatures. They are able to hover in place, and so are the only winged creatures that do not need to maintain forward movement in a battle.
The creatures can turn 180 degrees in a single round and can make one pass every round. this class includes pixies, sprites, sylphs, and most giant insects.
Class C includes most normal birds and flying magical items. Forward momentum must be maintained by moving at least half the normal movement rate (although some magical items are exempted from this). Creatures in this class can turn up to 90 degrees in a single round and can make one pass every two rounds. Gargoyles and harpies fall into this class. Dragons, although huge, are amazingly maneuverable and also fall into this class.
Class D creatures are somewhat slow to reach maximum speed, and they make wide turns. Forward movement equal to at least half the movement rate is required. Turns are limited to 60 degrees in a single round. Class D creatures make only one pass every three rounds. Pegasi, pteranodons, and sphinxes fall into this class.
Class E is for flyers so large or clumsy that tight maneuvering is impossible. The creature must fly at least half its movement rate, and can only turn up to 30 degrees in a single round. Thus, it can make just one pass every six rounds. This class includes rocks and other truly gigantic creatures.
===Levitation===
Levitating creatures don't truly fly, and their movement is generally limited to up or down. Levitating creatures that are able to move freely are assumed to be class A. Otherwise, the power does not grant any maneuverability and so is not assigned a class.
===Altitude===
The relative elevation of combatants is important for a variety of reasons, but as far as combat goes, it has little real effect. If flying creatures wish to fight, they must all be flying at approximately the same height. If one of the creatures flees and the others do not pursue, he gets away. Simple.
Altitude affects the action. The DM should keep the following guidelines in mind as he listens to what players want to do and decides how creatures and NPCs will react.
Creatures cannot charge those above them, although those above can dive, gaining the charge bonus.
Only creatures with natural weapons or riders with "L" weapons, such as a lance, can attack a creature below them. Attacks from below suffer a -2 penalty to the attack roll, as the reach and angle make combat difficult.
===Combat Procedure===
Aerial combat is based on maneuverability. When flying creatures fight, compare the maneuverability classes of the different combatants. If these are all identical, the combat is conducted normally. When maneuverability classes differ, creatures with the better class gain several advantages.
For each difference in class, the more maneuverable flyer subtracts one from its initiative die rolls. Its maneuverability increases its ability to strike quickly and to strike areas that are difficult to protect.
Breath Weapons are more problematic in aerial combat than on the ground. Creatures using breath weapons find their fields of fire slightly more restricted, making the attack harder to use. Dragons, in particular, find it difficult to use their breath weapons to the side and rear while flying forward.
Those within a 60-degree arc of the front of the creature roll saving throws vs. breath weapons normally. Creatures outside this arc save with a +2 bonus to the die roll.
Missile Fire is also difficult in aerial combat. Those mounted on a flying creature or magical device suffer all the penalties for mounted bowfire. Hovering is the same as standing still and incurs no penalty.
Characters using missile fire while levitating suffer a -1 cumulative penalty for each round of fire, up to a maximum of -5. Levitation is not a stable platform, and the reaction from the missile fire creates a gradually increasing rocking motion. A round spent doing nothing allows the character to regain his balance. Medium and heavy crossbows cannot be cocked by levitating characters, since there is no point of leverage.
===Air-to-Ground Combat===
When attacking a creature on the ground (or one levitating and unable to move), the flyer's attacks are limited by the number of rounds needed to complete a pass.
A dragon flies out of its cave to attack the player characters as they near its lair. On the first round it swoops over them, raking the lead character with its claws. Since its maneuverability is C, it then spends a round wheeling about and swooping back to make another attack on the third round of combat. Of course, during this time, its flight will more than likely take it out of range of the player characters.
===Escaping===
When a creature tries to break off from combat, its ability to escape depends on its maneuverability and speed. Creatures both faster and more maneuverable than their opponents can escape combat with no penalties. The free attack for fleeing a combat is not allowed, since the other flyer is also in motion (probably in the opposite direction).
If a creature is faster, but not more maneuverable, it can break off by simply outrunning its opponent. The other cannot keep pace. In this case, a free attack for fleeing is allowed.
If the creature is slower, regardless of maneuverability, an initiative roll must be made (modified by the maneuverability of the flyers). If the fleeing creature's initiative roll is lower than that of the pursuer, the creature has managed to flee, although suffering the usual attack for fleeing.
===Damage===
Any winged creature that loses more than 50% of its hit points cannot sustain itself in the air and must land as soon as possible. The creature can glide safely to the ground, but cannot gain altitude or fly faster than half its normal movement rate. If no safe landing point is available, the creature is just out of luck. Since the circumstances of a crash landing can vary greatly, the exact handling of the situation is left to the DM. The falling rules may come in handy, though a vivid imagination may be even more helpful.
== Aerial Combat (Optional Rules) ==
These optional rules provide more precision about just what is happening in an aerial battle. However, these battles require the use of miniatures or counters and generally take longer to resolve. All of the aerial combat rules above remain in effect except where specifically contradicted below.
===Movement===
Movement is measured in inches (1 inch = 10 feet of movement) and the pieces are moved on the tabletop or floor. The maneuverability classes determine how far a figure can turn in a single round. A protractor is handy for figuring this. Turns can be made at any point in the round, provided the total number of degrees turned is not exceeded in the round and there is at least 1 inch of movement between turns.
===Climbing and Diving===
Players keep track of the altitude of their flyers by noting the current altitude on a slip of paper. Like movement, this can be recorded as inches of altitude. A creature can climb 1 inch for every inch of forward movement.
Creatures of class C and worse have a minimum air speed, and they must spend at least half their movement rate going forward. Thus, they cannot fly straight up and can only climb at a maximum of 1/2 their normal movement rate.
Diving creatures gain speed, earning an additional inch to their movement for every inch they dive, up to their maximum movement rate. Thus, a creature able to fly 12 could move 24 by diving for its entire movement, since each inch of diving adds one inch of movement.
A diving creature must fly the full distance it gains diving, although it need not fly its full normal movement. A creature with a movement of 12 could not dive 9 and fly only 6 forward. It must move forward at least 9, the distance it dove.
===Attacking===
Since the exact positions of the flying units are marked by miniatures, several abstractions for aerial combat are not used. Die roll modifiers for maneuverability are ignored. These simulate the ability of more acrobatic creatures gaining an advantage over clumsier flyers. When playing with miniatures or counters, this task is left to the players.
Likewise, the number of rounds required to make a pass are not used, as this becomes evident from the position of the pieces.
When a diving creature makes an attack, it is considered to be charging. Charging creatures gain the normal combat bonus. Lances and spears inflict double damage in a charge. Further, creatures with talons or claws cause double damage when they hit during a dive.
== Underwater Combat ==
An oft-neglected, but fascinating, area for adventure is that great and mysterious realm that lies beneath the waves. Here, ancient civilizations, green and dark, lie waiting to be discovered. Vast treasure hordes are said to lie scattered and open on the murky bottom. Creatures, fearsome and fanciful, rule kingdoms unknown to man. Many are the mysteries of the ocean, but, to solve them, players must deal with some unusual problems.
===Breathing===
The biggest problem facing characters underwater is, naturally, breathing. Before any kind of underwater adventure is undertaken, they have to find some way to stay underwater for long periods. Characters can use magical spells or devices; they can use water breathing potions; they can even polymorph themselves into underwater creatures (although this might lead to other, unexpected problems). If none of these solutions seems workable, the DM can provide oxygen-supplying seaweeds or kelps the characters can eat.
Without some method of breathing underwater, the characters are going to have a very short adventure! Rules for holding one's breath (a short term solution, at best!) and drowning can be found in the Player's Handbook .
===Movement===
There are two basic ways to move in water—swimming or sinking like a stone and walking on the bottom. Rules for swimming can be found in the Player's Handbook. In rare cases, player characters may be able to find and use trained
mounts such as giant seahorses.
===Vision===
One major limitation of underwater combat is the lack of available light. In fresh water, vision is limited to a base of 50'. This is reduced by 10' for every 10' of depth. Characters exploring the depths of a murky lake, 50' below the surface, could see about 10'. Below this, the darkness would close in about them.
In salt water, which has somewhat less algae, the base extends out to 100', modified for depth in the same way as fresh water.
===Natural and Artificial Light===
The vision guidelines above assume a bright sunlight day on the surface overhead. On overcast days, the distance a character sees can be reduced by half or more. On moonless nights a character's range of vision is virtually nil.
Artificial light sources function underwater (although players will have to think fast to keep torches and lanterns lit). Artificial light sources illuminate half the space under water that they would light on the surface.
===Obscured Vision===
In addition to low light, vision can be obscured by seaweed, sea grass, and kelp forests. These hamper vision in much the same way as thick brush on the surface.
Schools of fish with their often silvery scales can reflect and scatter light in hundreds of different directions, creating a shining cloud of confusion. Even without the reflection, their darting forms obscure an area.
Finally, the ink from a giant squid, or even mud stirred up from the bottom, have all the effects of a darkness spell. Infravision and light have no success penetrating such murky waters.
===Infravision===
Infravision functions underwater, though not with the same efficiency as on the surface. In no case does it extend past the normal ranges allowed in dungeons. In addition, the sheer alienness of the environment makes it difficult for the character to be certain of all he sees.
===Combat===
The greatest factor in fighting underwater is overcoming the resistance of the water. Even though a weapon still retains its mass and density, the resistance of the water greatly weakens the impact of any blow. Thus, only thrust weapons can be used effectively underwater (except for those possessing magical items that enable free action).
Thrown and hurled weapons (except nets) are useless underwater. Of the missile weapons, only specially made crossbows can be used effectively underwater. Even so, all rangers on these weapons are reduced by half.
Nets are particularly effective in underwater combat. They tend to remain spread once opened, and characters should find them useful for close-in combat. Properly weighted, nets can be thrown by tossing them with a slight spin, so that the force of rotation keeps the lines taut. The range is very short, only 1' for every point of the thrower's Strength.
===Combat Problems of Surface-Dwellers===
In combat, surface-dwellers suffer special disadvantages when fighting the races of the sea.
Being unaccustomed to the water resistance and changed in apparent weight, surface-dwellers add four to their initiative tolls in hand-to-hand combat. This does not apply to missile fire or spellcasting. Surface-Dwellers also suffer a -4 penalty to their attack rolls, due to the slowness of their movements.
===Underwater Magic===
Spells are also affected by the underwater world. Not surprisingly, fire-based spells have no effect unless cast in an area of free oxygen (such as a domed city).
Electrical spells conduct their energy into the surrounding water. Thus, a lightning bolt originating 60' away from the caster acts like a fireball at the point of origin.
Spells affecting forces of nature not normally found underwater have no effect—call lightning, for example. Spells that summon or command creatures not native to the depths are also pointless.