As a skill, Cantus requires proficiency and uses whatever your spell-casting modifier is. If you do not normally cast spells, Cantus will use your highest mental ability modifier. You gain daily Cantus charges equal to one-half your level times your relevant modifier. Every spell-level is equal to 3 charges. Always round-down.
You may use your passive check on a task that doesn’t involve any distractions or pressures or is not time sensitive. Taking 20 depends on the check, as do retries. Any check to build or sense something may be 20/retried. Any check to know, learn, or perform a combat action may not. A check made to gather energy, manifest out of combat, or such may be retried, but usually not taken 20. Specific uses of Cantus vary by element. Passive Cantus checks may be required from time to time.
The Cantus elements are: Fire, Aurum (metal), Water, Ice, Desert, Forest, Electricity, Magnetism, Gravity, Wind, Crystal, Darkness, and Light. In rare circumstances all the elements may be combined or used as one and in this case the effect is considered to be of the Dragon element. Dragon is not an actual element, but when it arises it can be useful to treat it as if it were one. A user with proficiency in Cantus can only use one element.
All dragons are proficient with Cantus naturally with the element usually matching their color. Half-dragons are naturally proficient with the Detect and Identify uses of Cantus but other uses require training from Kal’Renth. Dragonkin/Dragonborn can use Cantus if they are raised or train on Kal’Renth which requires an Existence Salient. Other mortals generally cannot gain proficiency in Cantus beyond the Detect and Identify uses.
|Cast Spell||15 + Level|
|Absorb, Draw, or Replenish||15|
|Set Metamagic||15 + Level|
|Identify Spell||15 + Level|
|Identify Existing Effect||25|
|Use items||see item|
Spells: Cantus spells may be crafted on the fly by dragons or those with draconic heritage. Other mortals must spend time learning and developing the spell and should follow the guidelines for Spell Research.
Gems: Gems are similar to staves. They store spells and effects and have a finite number of charges. They can be recharged under specific circumstances. To use a spell requires a Cantus check with a DC = 15 + charges used. Treat Gems as staves when determining crafting details.
Pools: A pool may be a literal pool in the ground, or just an item that contains a reservoir of magical energy. Usually they take the form of jewelry, but can be any item or ornament worn on the body. The larger and more elaborate they are, the more powerful they tend to be, though this is not always the case. Notable pools are kept by the draconic temples and take the form of great statues. Pools may not be made in the form of any useful item such as weapons or armor or rings. Pools are element-specific and two elements cannot be mixed in a pool, nor can a mage of the wrong element use it. Any mage, however, may draw non-elemental energy from any pool.
A pool may store energy in the form of charges/castings. Generally, it takes 3 charges per spell level. There is no upper limit on how many charges may be stored in a pool, but usually it takes 200 gp per charge. Choice of materials may affect that. To use a pool as part of a casting, spell, or effect, a mage must succeed on a Cantus check with DC = 10 + charges used. To replenish or draw from a pool a mage must succeed on a Cantus check of 15. Using a pool to cast a spell or effect is a standard action or the length of the spell or effect, whichever is longer. Replenishing or drawing from a pool is a full-round action for every 3 charges added or removed.
Amplifiers: An amplifier is an item designed to assist Cantus users on their Cantus checks. It takes the form of a die banded with zorite and electrum. Amplifiers come in several varieties but they can be used by any Cantus mage regardless of element. They can be crafted in +1 to +8 varieties. Crafting them uses the same details of Rings of Protection. Amplifiers provide their bonuses passively so long as they are worn and they may be set into most jewelry, taking up that body slot.
Absorb/Draw/Replenish: These actions refer to either absorbing Cantus energy from an existing effect or from the surrounding area, drawing Cantus out of a pool and back into one’s personal supply, or using one’s personal supply to re-fill a pool. The drawing and replenishing actions are described above. Absorbing Cantus from an effect or from the surrounding area requires a Cantus check with DC 15 and takes a full-round action for every charge absorbed. Generally, 3 charges is one spell-casting.
Set Metamagic: If a mage has a metamagic feat, he or she may use it to inscribe a rune or circuit on a surface that, when a Cantus spell is channeled through it, applies the metamagic to the spell without requiring the use of a higher-level spell slot. Instead, the rune requires a number of Cantus charges equal to the spell adjustment of the feat (minimum 1). Each rune is good for one use but once crafted it lasts for a day. Using more Cantus a mage can make a rune that lasts longer or is good for more uses (such runes are called circuits).
A regular rune takes a minute to make, charges equal to the spell adjustment, and materials costing 10 gp. For a circuit that lasts a week: multiply charges by 1.5, materials cost 25 gp. For a permanent circuit: double the charges, materials cost 50 gp. To add additional castings add half of the original charges per additional casting and increase the crafting DC by 1 per additional casting.
For example: a circuit of Quicken Spell requires 4 charges to make and has a DC of 19. If you want to make it handle two extra castings, it requires an additional 4 charges to craft: 2 for each extra casting for a grand total of 8 charges to craft. The DC increases by 2 and is now 21.