The Bow And Arrow is the main and only weapon used by the protagonist in Titan Souls. Unlike many other games with the bow and arrow, in Titan Souls, the protagonist carries only one of each, and they are able to collect and draw-in their arrow with an ability similar to telekinesis. This also pulls the protagonist towards the arrow on certain surfaces, like ice, by Newton's third law. It is suggested by The Elder that the Arrow itself is somehow special and that the protagonist had done something potentially terrible to gain it, The Elder referring to it as an "abomination". It is never revealed in the game what this is, though at the beginning of the game three souls are absorbed by the protagonist, the bow and the arrow. The origin of these souls is unknown (they may be fragments of the protagonist's own soul or other titans' souls), but they are likely what gives the arrow its power to kill titans and allows the protagonist to recall it.
There are two other characters with their own Arrows. Knight Elhanan has enhanced control of his special arrow, as well as possessing additional, seemingly mundane arrows. The Soul has its own Arrow, this one glowing bright white, as well as possessing the ability to control the protagonist's arrow. The protagonist's telekinetic control of his own arrow also affects the Soul's special arrow, although the protagonist dies upon contact with this arrow, suggesting some special manner of ward or other magical effect that we are not aware of.