Cover

Rule: You can strike cover instead of the intended target if you miss the target by no more than the cover bonus and you hit the cover itself with a second attack roll (critical threat doesn’t apply, though automatic hits and misses do). Concealment is applied before this roll; thus if you fail to hit due to concealment, you don’t hit anything significant.

Change: The variant listed in the DMG does not require a second attack roll and actually allows you to then hit the original target.

Damage Reduction/Magic

Rule: DR/Magic works on a scale of 5 points per +1 enhancement bonus. So, a +1 weapon overcomes 5 points of DR/Magic, a +2 weapon overcomes 10 points of DR/Magic, etc. A creature with DR/Magic overcomes a similar amount of DR/Magic. For example, a creature with DR 5/Magic overcomes the DR of another creature with DR 5/Magic entirely, but only 5 points from the DR of another creature with greater than DR 5/Magic.

Change: DR/Magic is otherwise pretty much useless beyond maybe 3rd-level. This is a simple change to make to give more power for DR and to give more credence to higher enhancement bonuses on weapons.

Massive Damage

Rule: There are no massive damage rules.

Change: Anything that removes the chance of instant kills is good for the game. This isn’t Unreal Tournament with InstaGib. Further, massive damage rules ascribe a certain level of “realism” to hit points which doesn’t work because hit points themselves are abstract. 50 hps to a barbarian is not the same thing as 50 hps to a wizard, thus rendering any logic to this rule irrelevant. If they were the same thing, then the barbarian would not have more hps, thus also removing any logic.

Underwater Combat

Condition: These represent the method in which you plan to move through the water. If multiple conditions apply, use the one most favorable to you for the given column. This table applies when wading in water at least waist deep, swimming, or walking along the bottom of a body of water. Creatures in the last category are generally those that fail their Swim Check or that cannot make a Swim Check (though in the latter case, these penalties are generally the least of their concerns).

Attacks: The penalties and damage for attacking with slashing and bludgeoning manufactured weapons are listed in the table below and depend on your condition. The penalties and damage for attacking with piercing or natural weapons are also listed and are generally more favorable because it’s easier to attack underwater with piercing and natural weapons. Unarmed attacks are not considered natural weapons for the purposes of this table. The penalties listed also apply to special attacks and their special attack rolls, such as tripping, grappling, sundering, and disarming.

Speed: The Speed you have underwater depends on whether you have a Swim Speed or if you have Freedom of Movement, or other modifiers as listed in the table below. Maneuverability in the water is always considered perfect except that Reverse costs 5ft of movement unless you have a Swim Speed or Freedom of Movement. If you have Firm Footing due to bracing against a wall then obviously you can’t move.

a. The Speed you have while under the effects of a Freedom of Movement uses your best movement mode, your choice.

b. The speeds listed are standard for the Swim skill (you can move one quarter your speed as a move-equivalent action or one-half your speed as a full-round action. To avoid the off-balance penalty (see note below), you must succeed at a Swim check (DC 5+ the DC for the water). The effects of a successful check last until your next turn (initiative count). Making the Swim check requires a move action; whether or not you actually move anywhere (so treading in the water requires a move action).

c. Creatures have firm footing when they walking along the bottom, braced against a wall, or the like. You can walk along the bottom only if you carry enough to weigh you down. The amount of weight required depends on your size, as follows: Fine 1 lb; Diminutive 2 lb; Tiny 8 lb.; Small 32 lb.; Medium-64 lb.; Large 256 lb.; Huge 512 lb.; Gargantuan 1024 lb.; Colossal 2096 lb. The items you carry to weigh yourself down must be non-bulky and non-buoyant. Consider most normal adventuring gear (except weapons) not to fit within this category.

d. Off-balance creatures lose Dexterity bonuses to Armor Class and give opponents a +2 attack bonus against them.

Fire: Non-magical fire (including alchemist’s fire) does not burn underwater. Spells or spell-like abilities with the fire descriptor (or that cause fire energy damage) are ineffective underwater unless the caster makes a successful caster level check (DC 25 + spell level). If successful, the spell creates a bubble of steam instead of its usual fiery effect (or appropriate descriptive effect). Additionally, the range of the spell is halved, the DC (if any) is at -2, and damage is at -1 per die (and half static bonuses). Supernatural and item fire effects are ineffective underwater unless their descriptions state otherwise. Artifacts are unaffected by the water.

The surface of a body of water blocks line of effect for any fire spell. If the caster has made a Spellcraft check to make the fire spell useful underwater, the surface also blocks the spell’s line of effect. For example, a fireball cast underwater cannot be targeted at creatures above the surface, nor can an underwater fireball spread above the surface.

Extraneous effects of fire spells are lost. For example, flammable items do not catch fire and metals with a low melting point do not melt. Damage done to objects can still cause them to break, however.

Attacks from Land: Characters swimming, floating, or treading water on the surface, or wading in water at least chest deep, have cover against melee or ranged attacks form landbound or flying opponents. A completely submerged creature has total cover (and possibly concealment) from them. Landbound or flying opponents who have freedom of movement ignore this cover when making melee attacks (but not ranged attacks). Magical effects remain unchanged, except for fire effects and effects that require attack rolls; these are treated like any other effects.

Ranged Attacks Underwater: Thrown weapons are ineffective underwater, even when launched from land, except for piercing thrown weapons. Ranged weapons (that are allowed) suffer a –4 attack penalty for each 5 feet of water they pass through, in addition to the normal penalties for range. However, even most ranged weapons cannot be fired under water. The water impedes the string in a bow and the twirling motion for a sling, for example. Thrown piercing weapons suffer no penalty for the first 5ft of water they pass through if the weapons are thrown from land or with a freedom of movement effect or Swim Speed.

Underwater Visibility: Submerged or swimming creatures may gain concealment from the water, depending on how clear it is. Underwater visibility will be given by a maximum sighting distance. The concealment provided by the water is then a factor of that distance. Beyond the sighting distance, creatures and objects have total concealment (by definition). From half the distance to the maximum, normal concealment (20%) is provided.

Aquatic creatures can see twice as far through the water as other creatures (but twice 0 feet is still 0 feet).

Invisible creatures displace water and leave a visible, body-shaped “bubble” where the water was displaced. The creature still has normal concealment (20% miss chance).

Change: The entire underwater combat rules section needs a revision. The rules presented here were modified from a combination of the 3.5 rules and the Return to the Temple of Elemental Evil web enhancement.