Magic and Rituals

Magic & Rituals

How spells work, casting checks, cantrips, and ritual casting in Stygian Depths.

Magic Basics

Spells Per Day (Not Spell Slots!)

  • You don’t have traditional spell slots.
  • When you successfully cast a spell, you can cast it repeatedly until you fail the casting roll.
  • When you fail to cast a spell, you lose that spell for the day.
  • Each spell you know can be cast multiple times per day as long as you keep succeeding on your casting checks.

Casting a Spell

Standard Casting

  1. Choose a memorized spell you know.
  2. Declare you’re casting it (uses your action in combat).
  3. Roll 1d20 + INT or WIS modifier.
Example: You’re a level 3 Arcanist casting Elemental Sphere (Journeyman level = spell level 1) with one fire rune attached. You need to roll 1d20 + INT vs. DC 12 (10 + 1 for spell level + 1 for rune). You roll a 9 + 3 (INT) = 12. Success! The spell works, and you can cast it again later.

Spell Attack Rolls

If your spell requires hitting a target (not an area effect):

  1. First, make your casting check to successfully cast the spell.
  2. If successful, THEN make an attack roll to see if you hit the target.
  3. Roll 1d20 + INT/WIS modifier vs. the target’s AC.
Note: Area effect spells don’t require attack rolls — they just affect everything in the area.

Cantrips

You can create minor magical effects related to your known spells at the DM’s discretion, without rolling or losing the spell.

  • These are for utility and flavor, not combat-level power.
  • Your DM decides what’s reasonable.
Examples (based on actual spell descriptions):
  • Mage with Elemental Sphere: Can create tiny flames or sparks.
  • Shaman with Cure: Can diagnose minor ailments by touch.
  • Arcanist with Detect Magic: Can make small objects glow faintly.

Ritual Casting

Any character who knows a spell can cast a more powerful ritual version.

Standard Ritual

  • Takes 10 minutes per spell level.
  • Try to meet DC 10 + spell level.
  • Each metamagic rune attached adds +1 to DC.
  • Success: Spell works as described; you can cast it again later.
  • Failure: Spell fizzles; you lose that spell for the day.
  • Natural 1: Miscast! Roll on the miscast table.

Open-Ended Ritual

  • GM adjudicates time, DC, materials needed, and requirements.
  • Allows creative magical effects related to spells you know.
  • Example: A mage with Fireball performs a ritual to burn down a building.
  • Success depends on the DM’s judgment of the situation.

Spell Schools

There are 8 spell schools, each with different themes. You must spend 3 talent points to open a school before you can learn any spells from it:

  • Warding: Protection, healing, dispelling
  • Destruction: Damage and smiting
  • Creation: Making objects and creatures
  • Perception: Detection and divination
  • Manipulation: Mind control and commands
  • Transmutation: Changing forms and properties
  • Temporal: Teleportation and time effects
  • Malady: Curses, diseases, and afflictions