The character with this skill gains the ability to imbue a weapon with an offensive spell, and to trigger any such imbued spells. The character must know the spell in order to imbue it into a weapon (you can't imbue from a Spellgem).
The spell will trigger on a successful hit if wielded by anyone who has Martial Spellcraft, as long as they have 1 MP, even if the wielder doesn't know the spell.
This ability costs 5 Action Points and three times the Magic Points needed to spontaneously cast the spell. The weapon will be imbued with the spell for its next 10 attacks. The spell is tied to the weapon and is not affected by Status Ticks.
If the weapon cannot be enchanted it cannot be imbued with a spell.
An imbued spell is subject to death decay in the same way as an enchantment.
Although imbued spells are technically enchantments, a spell can be placed on a fully enchanted weapon and will not count against the maximum number of enchantments that can be placed on a weapon.
Only one spell can be imbued in a given weapon at one time. Imbuing it with a new spell will overwrite any previously imbued spell.
Use of Weapons
Only characters with Martial Spellcraft are able to trigger an imbued spell. Each attack they make with an imbued weapon costs them 1 MP.
A successful hit will trigger the spell, doing half its base damage as Supplemental Damage. The imbued spell does not gain any damage bonuses whatsoever, nor will it stack with other supplemental damage sources such as Frost Charge. Note: Remember that the supplemental damage from the Wizard's aura will not stack with the supplemental damage from Martial Spellcraft. See the page on Supplemental damage for more information.
Other characters can use the weapon normally, not paying the extra MP nor being able to trigger the imbued spell. Such attacks still count against the 10 attacks before the spell dissipates.
Imbued spells, as with all other forms of supplemental damage, are ignored for purposes of skills such as Tattoo of Adaptation.
Moe the Wizard wants to imbue his Carving Knife with a Sunflare spell. This will cost him 5 Action Points and 21 Magic Points (3 times the normal 7 MP casting cost). His next 10 attacks with the knife will each cost 1 MP. He also gets drunk to give himself +1 damage with all close-combat attacks. If he successfully scores a hit, the target will take 4 Slashing damage (3 base damage from the knife plus 1 from being drunk) and 6 supplemental Fire damage (from the Sunflare spell, half damage, no bonuses).
Moe the Wizard imbues his knife with a spell. He then passes it to Larry, an Eternal Soldier. Larry, not having Martial Spellcraft, swings the Knife 10 times. It does not cost him Magic Points, but his hits don't trigger the imbued spell either, so he doesn't deal any extra damage. Since he attacked with the weapon 10 times, however, the imbued spell dissipates.
Moe the Wizard imbues his knife with a Sunflare spell. He then passes the Knife to Alice, a Holy Champion who does have Martial Spellcraft. Alice will use 1 Magic Point on each of her next 10 attacks with the knife. If she hits, it will trigger the spell and deal 6 supplemental Fire damage in addition to the Knife's normal Slashing damage, even if Alice never learned Sunflare.