Rune Dragon (Young, Spellcaster)
CREATURE 10Rune dragons have an innate insight on the power of runes. Most rune dragons keep a variety of runes etched on their scales, which their bodies can magically empower. They typically don't cast spells themselves, instead relying on their ability to create runes on the fly to produce desired effects. A rune dragon often refers to their hoard as their library, as it's full of important historical texts, plays, speeches, textbooks, and spellbooks written by people of different cultures in a variety of languages. While they can often speak a language with the aid of magic, they much prefer to learn languages in the context of their speakers so they can grasp the nuances hidden within the syntax and the magic within their symbols.
The rune dragon is aware of any active magical abilities and effects within the listed range. When the dragon Seeks, it gains the benefits of a 4th-rank detect magic spell within the listed range (in addition to the normal benefits of Seeking).
The rune dragon's scales function as runestones. The rune dragon can't use the effects or abilities of the runes etched on its scales, but they can transfer these runes to appropriate objects. Transferring a rune to or from an item in this way requires 1 minute, during which the dragon is Off-Guard. The process is automatic and doesn't require a check, but if the dragon stops or is interrupted in this process, the rune is destroyed. A rune dragon can have any number of runes etched on its scales, though they typically have only a handful of runes etched on their scales at a time.
The rune dragon's Strikes and abilities can leave a detonating rune on their targets. If a creature would receive a detonating rune while they already have one, instead of adding another rune, their current detonating rune activates, dealing 4d6 damage to the target and expending the rune. The detonating rune's damage type matches the dragon's current Shifting Rune. A creature can use an Interact action to remove the rune. Detonating runes fade after 1 minute if not detonated.
The dragon launches hundreds of exploding runes that detonate upon impact, dealing 9d6 damage in a 30-foot cone (DC 29 basic Reflex save). The damage type of this ability is determined by Shifting Rune. Creatures who fail the save are also affected by detonating rune. The dragon can't use Runic Breath again for 1d4 rounds.
The rune dragon chooses between acid, cold, electricity, fire, or sonic damage. The runes etched upon the dragon shift, forming runes of that energy on its scales. The dragon gains immunity to that damage type, and their detonating runes and Runic Breath deal that damage type. Anyone trained in Arcana can immediately recognize the energy type of the etched rune without a check.