Thor's Hammer is a bow made out of a material emitting a soft yellow glow. There are various orbs which line the bow, possibly made out of topaz or amber judging by the items used to upgrade Thor's Hammer. There are three on both sides of the bow, along with two on the grip and two holding the string. The arrow is made from the same glowing material.
Thor's Hammer gives a good Magic Attack alongside a moderate bonus to Attack. Despite being nowhere near as large as the Eagle Eye, the Thor's Hammer provides a sizable boost to Accuracy, with the second highest Accuracy boost in all games it appears in. The Thor's Hammer specializes in stunning foes, as not only can it inflict Stun on foes with its weapon-elemental attacks, but it can also do so with its bonus/auto skills. This combination causes the Thor's Hammer to be able to fairly often stun foes.
When fully upgraded Thor's Hammer resists Thunder, and grants immunity to Stun in both games. In EBF5 it also grants resistance to Wind.
Note: Stats in brackets (below/right from actual) are for its pre-v2 update version. Before the v2 update, resisted Light/Heavy instead of Wind, casted Spark Shower (50 power and 66% multiplier) instead of Thunderstorm, and didn't have an unleash.