Characteristics
One of the most obvious differences between Eberron and generic D&D is the level of magic. High-level magic, including resurrection spells, is less common than in most other settings. However, low-level magic is much more pervasive, primarily provided by the Dragonmarked houses. Many cities have magical lanterns throughout the streets. A continent-spanning, magical "lightning rail" provides high speed transportation.
Alignment is slightly more muddied than in other official settings. Evil beings of traditionally good races and good beings of traditionally evil races are encouraged; but alignment definition remains true to D&D standards, with good and evil retaining their meanings. However, the situation often arises in the campaign world that oppositely aligned characters will side with each other briefly if a threat looms over all, and also both good and evil characters will infiltrate each others' organizations for purposes of espionage.
Religion is similarly less clear-cut. The pantheon of Eberron does not make itself overtly known. The existence of divine magic is not evidence of the gods, as clerics who worship no deities but instead follow a path or belief system also receive spells. A cleric can even actively work against their own church and continue to receive spells. As a result, religion is largely a matter of faith. Unlike in many other 3rd edition D&D settings, a cleric does not have to be within one step of his deity's or religion's alignment, and is not restricted from casting certain spells because of alignment.
The setting adds a new base character class, the artificer. Artificers are spellcasters focusing on magical item creation. Artificer infusions (their equivalent to spells) focus on temporarily imbuing objects with the desired effects. For example, instead of casting bull's strength on a character, an artificer would cast it upon a belt to create a short term magical Belt of Bull's Strength. Artificers have access to a pool of "craft points" which act as extra experience points (only) for use in creating magical items without sacrificing level attainment. This pool is refilled when the artificer gains levels, or by draining power from an existing magical item (destroying the item in the process).
Eberron also introduces a new NPC class known as the magewright, which is an arcane caster who has a limited selection of low-level spells. The existence of magewrights is part of the reason for the prevalence of low-level magic in Eberron.
To try to create a pulp setting, Eberron uses "action points" that allow a player to add a six-sided die to the result of rolls made with a twenty-sided die. Characters receive a set allotment of single-use action points each character level. The Eberron Campaign Setting also includes feats which grant additional uses for action points, such as allowing a player to add an eight-sided die instead of a six-sided die, or spending two action points to grant your character an additional move or standard action. Certain class features with uses per day, like a barbarian's rage ability, a cleric's turn/rebuke undead ability, or a druid's wild shape ability, can be used again by spending 2 action points. The final use for action points is to spend one to stabilize a dying character.
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