Tuning Forks

These small, forked rods are a simple design, but often crafted with an artisanal prowess that shows through despite its basic form. They can be made with a myriad of materials, from the mundane to the extraordinary, and the importance of their use (and consequence of an improper make) means that often no expense is spared in their crafting, for these rods are the keys that unlock the door to extraplanar travel.

Description

At its most basic, a tuning fork is a small, two pronged fork that vibrates when struck, playing a specific note of sound. Most are made from metal, though a few are made from crystals. A typical fork is six to eight inches long, including the handle. While not necessary to their function, the cost and skill required to craft them to the precise specifications needed for proper use means that they are often made to be quite ornate, featuring delicate and intricate inscriptions, embossing, and other decoration. Many of these forks are works of art in and of themselves, giving them great value beyond their function. While a basic tuning fork can be made for as little as 50 gold, few would risk their lives on the use of one so cheap unless they had no other option, and one could commonly expect to pay in the range of 200gp - 500gp for one of more reliable make. Tuning forks are known to be made from the following materials, though more obscure ones may exist of more exotic materials:

Steel
Copper
Zinc
Lead
Tin
Bronze
Brass
Spelter (a Zinc-Lead alloy)
Pewter
Glass
Quartz
Platinum
Silver
Gold
Nickel
Iron

Use

Tuning forks are a necessary component of the powerful Plane Shift spell. This spell serves as a primary means of reliable inter-planar travel, and cannot function without one or more precisely crafted tuning forks. It is for this use that they are referred to as the keys to the planes. When struck as part of the casting of Plane Shift, they orient the spell to target the plane corresponding to the fork. Each destination requires a specific type of fork to reach, both in material and pitch, and many destinations require multiple forks used in unison (or a fork designed to emit a complete chord when struck). The destination of the spell is beyond the control of the caster, instead driven entirely by the fork used in its casting. A slight deviation on the proper note can cause the spell to fail or, worse, target the wrong destination. It is for this reason that most tuning forks are made to exacting specifications by skilled artisans; the risk of failure is rarely worth the coin saved from a fork made quick and cheap. Many are stylized to match their destination plane, reducing the likelihood of using the wrong fork by mistake.

Researching Forks

Whilst it is well known (at least to those capable of the magic requiring their use) that these forks are required in the casting of the Plane Shift spell, Which forks correspond to which destinations are often closely guarded secrets, and the more obscure knowledge of the destination is the more obscure the knowledge of its tuning. If knowledge of the specific fork needed to reach a plane is not known, one wishing to use the spell would have to perform research to determine it. Any spellcaster able to cast the Plane Shift spell has knowledge of the fork required for their native plane. Researching tuning forks operates much like Spell Research, requiring access to research material related to their spellcasting class to perform. The cost and time required to research the fork needed for a destination depend on the type of destination (inner/outer plane, demiplane, or alternate material plane), as well as the obscurity of knowledge of the plane in question (location dependent).The typical cost to research a given location can be found in the Research Cost Table below. When performing research into the fork for a specific location, a Knowledge (planes) check must be made. The result of this check applies a multiplier to the time and cost required, as shown in the Check Multiplier Table below. Once made, a check cannot be re-rolled for a specific location until the character obtains a new level of experience. If a character decides to abandon their research or attempt to research a different location after rolling the check, they must still expend 1/10th the base time and cost of the research (this expenditure does not count towards their progress). All research requires a minimum of one day to perform.

Research Cost Table

Destination Type/Obscurity	Research Cost (GP)	Research Time
Transitive Plane	500 gp	2 days
Inner Plane (Common)	500 gp	2 days
Inner Plane (Obscure)	1,500 gp	2 weeks
Outer Plane (Common)	1,000 gp	1 week
Outer Plane (Obscure)	3,000 gp	1 month
Demiplane (Common)	5,000 gp	1 month
Demiplane (Obscure)	15,000 gp	6 months
Alternate Material Plane (Common)	750 gp	2 weeks
Alternate Material Plane (Obscure)	3,000 gp	2 months

Check Multiplier Table

Check Roll	Time and Cost Multiplier
9 or lower	4
10 - 19	2
20 - 29	1
30 - 39	1/2
40 - 49	1/5
50+	1/10

Crafting Forks

Crafting a tuning fork requires a Craft (blacksmithing) check for any fork made of metal, a Craft (gemcutting) check for any crystal forks, or a Craft (glassblowing) check for a glass fork. The DC for any given check is 15. A reasonably related Craft check can be made in lieu of the standard check (i.e. armorsmithing or weaponsmithing in place of blacksmithing), but the DC increases by 5 for such checks. The price of a fork is 50 gp. If any check is failed in the crafting of a tuning fork, the note is imperfect, and the fork will cause a Plane Shift cast using it to fail 10% of the time. If any given check fails by 5 or more, it is deeply flawed, fails 20% of the time, and plays the wrong note (thus targeting the wrong plane) 10% of the time. A tuning fork purchased at its market price has a 50% chance of being flawed and a 20% chance of being deeply flawed (can be determined with a successful Appraise check). If a tuning fork is successfully made masterwork (at a cost of 300 gp with a Craft DC of 20), the fork has no chance of failure regardless of failed checks while crafting.