This permanent, magical device converts spell energy to motive power, lift capacity, and sometimes other vessel-wide spell effects. Usually crafted as a large black box (1-cubic-yard, weighing 800 pounds), a dynamo of flying can function anywhere on board a ship. For convenience and safety, it's typically secured in the vessel's control area. A dispel magic attack by a Spellcaster may cause the dynamo and all spell effects powered by it to “go down” for idle rounds. For this reason, a vessel rarely relies solely on her dynamo for lifting capabilities.
Dynamos of flying are usually tailor-made for a specific vessel. They may be enchanted with multiple effects: fly, teleport, travel, invisibility, dimension door, and so on. The user chooses which effects to activate.
To power a dynamo of flying, the user must cast a spell on the device. This requires physical contact, but can be done with any spell-even those that create something, such as a form spell, and those that normally affect the caster only. It does not work with spells cast from scrolls or other magic items. The dynamo gains the equivalent of one charge per level of the spell cast upon it. It can store up to 50 charges at a time.
Each spell effect the dynamo creates costs one charge per spell level. (For example, fly costs three charges, while travel costs eight charges.) Duration of effect is the same as though cast by an 18th-level Spellcaster. (If the enchanter's level is known, use that instead.) Dynamos of flying come in different strengths.
- A lesser dynamo can power vessels only up to 50 tons. Moving larger ships with a lesser dynamo requires twice the normal number of charges per spell effect for a 100-ton vessel; three times the number of charges for a 150- ton vessel; and so on. Cost to enchant a lesser dynamo is halved.
- A normal dynamo can power vessels up to a Tonnage of 150. Affecting a 300-ton vessel costs twice as many charges, as explained above.
- A greater dynamo can power vessels up to a tonnage of 450. Cost to enchant a greater dynamo is doubled.
If the dynamo is used to provide lift as well as motive power, its lift capacity is double the tonnage of the ship. Charges used and spell durations are like other spell effects.
A dynamo's user can elect to spend more charges to increase the vessel's air speed past the normal maximum of the spell involved (fly, similar spells). Each increase costs the same number of charges as evoking the effect, in return for a 20% increase in air speed-and a 20% chance the dynamo will malfunction, losing all charges for 1d6 days. Doubling air speed costs five times as many charges as the initial effect, with a 100% chance the dynamo will be unusable for 1d6 days once the effect's duration ends.
Spellcasters enchanting a dynamo of flying must know spell turning (the base spell for creating a dynamo), as well as any spell the dynamo of flying will need to provide. Dynamos of flying must be made permanent.
Examples: A dynamo of flying enchanted with fly and shield by an 18th-level Spellcaster can lift and fly a 100-ton skyship for 19-24 turns per three charges used. Using an additional charge to activate the shield improves the vessel's AC by 1 for two turns. A particularly impressive greater dynamo might use fly for normal flight and teleport or travel for special situations. It may also be enchanted with other effects-shield, invisibility, haste, antimagic shell, and weather control. (Such a powerful device is extremely difficult to create and phenomenally expensive to acquire.)
Optional Rule: If the DM wishes, a dynamo of flying can make even a nonmagical vessel fly. This is especially appropriate if you use the optional rules allowing wizards to enchant normal vessels and buildings to fly.