Sometimes a bard gets tired of trying to remember every single important spell, or having to choose over powerful high level spells and abundant low level support spells, and only having the ability to switch out their spells when they become significantly stronger is incredibly limiting. So some crazy bard convinced some insane artificer to craft this device for them.
This device resembles a "Pin Stopper Music box" utilizing a spinning metal tube with embossed bumps that run over metal pins which causes a note to be played. However these metal tubes are specially crafted to hold a "memory" specified by the attuned creature. These memories can remind the attuned bard of the way that they cast certain spells.
Crafting Spell Dials - A spell dial is an electrum tube (or Dial) which contains an emerald core. The dial itself costs 50gp worth of electrum as well as time to emboss it so that it plays the correct song. in addition to the electrum dial, an emerald worth (50gp x the level of the spell which you want to attune to the dial) is required.
Attuning Spell Dials - To attune a spell to a dial, the user must attune to the dial and the dial will store the "memory" of the next spell cast by the attuned creature, as long as the dial is crafted to contain said spell level. Once a spell has been cast by the attuned creature, and it is stored in the dial, the attunement to the dial breaks.
Using Spell Dials - As part of a long rest a bard can play any amount of spell dials replacing a memorized spell with the one contained within the spell dial.
By design, the dial itself is most important component. Because the psychically tuned emerald is stored within the dial itself, it can be played on any music box built to play a dial. Of course the clockwork timing of music boxes can be slightly off as there is no standard timing for these devices, but anyone with a set of tools can adjust this.
Notes: Requires attunement from a bard
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