The ability to form a spiritual bond with other creatures is a gift taught to the mortal races by the Dragons. In theory, anyone may learn to do this, but there are mental and spiritual limits to how great a creature one can bond with, and for how long.
Many class features and spells represent forms of the bond. Familiars, Animal Companions, and Paladin mounts are common forms. Even a wizard that bonds with an object is learning to connect with it’s unawakened spirit.
The ability to command summoned creatures, mindless undead, constructs, and the like is based off the same principle magic, but does not represent an actual bond, although new feats and spells will allow players with the bond ability to enhance these in various ways.
For details on the feats and skills involving the bond, see the Feats and Skills section.
Characters may have multiple bonds, and frequently do. The bond works two ways and allows either party to attempt to exert some control over the other. These bonds are usually with weaker creatures and establish some degree of dominance over the creature. In some cases the bond is with a creature with equal or greater power than the character, and in that case the bond typically evolves into a working partnership, or a constant power struggle.
Bond strength: All bonds have a strength rating. In the cases of summoned or commanded creatures the bond is strength 0. Bonds granted by class features are strength 1. Bond strength comes into play in a number of ways, and many feats require a bond with a minimum strength.
Bonds and dominance: Bonds granted by a class feature are always established with the character dominant. However, many feats which enhance these features may require the character to allow the bond to work both ways, and opens the possibility that the creature or object may influence the character.
In all cases, only one member of each bond may be dominant at a given time. In most cases neither is at any given time, however when using an ability that effects the target of the bond (such as share spell), dominance must be established. This may be resisted by the target (see skills). If the bond is with an object, the object is always considered non resistant, unless it is intelligent. Feats that grant abilities over the bond will state if they require one side or the other to have dominance. In the case of bonds between two powerful and intelligent creatures that work together dominance is usually granted freely as needed by either side.
Balancing multiple bonds: Creatures may have any number of bonds, provided they have the feats and class features to support them. In most cases this is not an issue, however attempting to communicate with or control multiple creatures at once can be difficult. In general a creature may only use one ability that requires some form of activation or establishing dominance each round. However abilities that are automatic (alertness for a familiar within arms reach) or that continue after activation continue to function normally. A character may normally only receive communication from one such source at a time, but they may choose to send any communications from themselves along as many bonds as they wish, provided the bond allows that type of communication. Some skills and feats may alter this. For instance, a wizard with the Extra Familiar feat has two raven familiars out scouting. He may receive empathic input from only one each round, how ever if he wished to communicate a sense of caution, he could choose to send it to one or both. If he also had an animal companion, he would be unable to send it the sense of caution, as animal companions normally lack empathic communication.
Breaking bonds: Bonds are generally assumed to last until one party or the other dies, but they don’t have to be. In most cases a bond will give limitations on its release or the replacement of a bonded creature or object that is killed or destroyed. All associated times and costs are multiplied by bond strength. In all cases, either party may attempt to sever the bond, with or without the consent of the other party. This can be difficult even if both parties are willing, and is very difficult if one party resists. If one party resists, the other party may only break the bond if it establishes dominance. Breaking a bond, willingly or unwillingly, has consequences. Both parties receive a penalty to all d20 rolls equal to bond strength -1 for a number of days equal to the bond strength. If the bond was severed do to the death or destruction of one party, the other party must make a will save, DC 10 +5 per point of bond strength, or the penalties duration becomes weeks instead of days. See skills for more information.