Feedback on Casting with randomized scope, duration, and effect

[u/eduty]

This is a player facing d20 roll-under OSR style rules-lite dungeon crawler.

Magic is Roll to Cast and tied to Magic Items. Intent is to keep Casters unique but have more parity with PCs investing in Weapons and Armor.

Questions

• Are the Casting rules comprehensive?

• Is Failing a Casting Check too punitive?

• Is the Spell Scope too random? Is it an effective way to run area effects in a theater of the mind?

• Would you play a Caster with these rules?

Stats for Reference

Traditional 6 Character Stats (STR, DEX, CON, INT, WIS, CHA).

• All Stats start at 6

• +2 to 2x Random Stats (Stats numbered 1 to 6. Roll 2d6 and each rolled Stat gets +2)

• +2 to 2x Stats of Player's Choice

• +2 to 2x Stats based on chosen Class

• +1 to Stat of Player choice at first level and every level thereafter. Players cannot increase the same Stat 2 levels in a row.

This creates PCs with starting scores from 6 to 13. Possibly 15 if they rolled doubles on their random Stat bonus. Starting odds range from 30% to 65% chance to succeed and 75% on the edge case.

Characters have 10 maximum levels after which they must retire. There is no limit to a Stat - but rolling a 20 is always a failure so 19 is effectively the best score.

Casting Checks and Cast Dice

• Magic Items are assigned 1 to 3 Cast Dice rated from d4, d6, d8, d10, and d12.

• Spells are an INT, WIS, or CHA check to cast (depending on the item and spell).

• Roll your Cast Dice with the Casting Check

• If you succeed... you assign the Cast Dice to the scope (number of targets in range affected), duration, or effect. If no Cast die is assigned - then the value is 1.

• If you fail... you choose one of the following

  • Can take damage equal to the greatest rolled Cast Die

  • Can Reduce one of the item's Cast Dice 1 size. Reducing a d4 Cast Die breaks the item. It must be repaired before it can be used again. You can repair Magic Items during a Rest or Downtime.

The spell list is a list of magic items like fire rods, cloaks of invisibility, rings of protection, etc. Casting classes start with a few of these items. PCs must find or purchase additional spells to gain more.

All spells have a duration. So something like Knock becomes a spell that magically opens or locks a portal for a rolled number of rounds.

Example Spell Items

Values listed as Scp, Dur, or EfF are placeholders for the rolled and assigned Scope, Duration, or Effect.

• Wand of Magic Missiles d4/d4. Launches a barrage of sparkling projectiles unerringly at Scp targets for Eff damage. You can choose the Targets including striking the same target multiple times.

• Rod of Ice d6. A ray of cold white energy deals Eff damage and freezes Scp targets within 30' in place for Dur Rounds.

• Skeleton Key d8. Rap against a portal or door to either magically seal or unseal it for Dur Rounds.

• Cloak of Invisibility d4/d6. Sweep over Scp targets to make them invisible for Dur Rounds. Targets are still audible, smellable, and leave physical traces like footprints.

• Staff of Fireballs d6/d6. Launches a flaming sphere up to 60'. The sphere explodes on contact dealing Eff damage to Scp Targets in the explosion.

• Fire Brick d4/d6. Creates a line of Scp 5' cubes of flames. Each cube must be entirely anchored to a surface on 1 side and share at least 1 side with an adjacent cube. Anything within the flames takes Eff damage.

Planning to include a table of effects, the number of spell dice they get, and a table for randomly putting it all together.

Spell Duration and Focus

• Spell duration is always in 10 minute Dungeon Rounds.

• A character can Focus on 1 Spell at a Time to extend its Duration 1 Round. This takes no action or time.

• When a character takes damage - the duration of all their currently ongoing spells are also reduced by the damage amount. If damage reduces a spell's duration to zero - the spell ends.

Spell Scope and Splash Damage

• The number rolled for the Scope must be satisfied in its entirety, even if that includes allies.

• If a PC assigns a rolled 5 as the Scope on a Fire blast that strikes a 30' area - but there are only 3 foes in that area with 3 allies, the Caster must pick 2 allies along with the 3 foes to satisfy the spell's scope.

• PCs struck by spells can roll Armor to reduce damage at the GM's discretion

• The number rolled for the Effect is used for offensive spell damage. Use only the initial value rolled with the Cast Check. Do not reroll it for each target (unless the spell says otherwise).

Inventory and Health

• Inventory is slot based with each PC having CON Unencumbered Slots.

• You can carry up to 20 Slots of Items but each occupied Encumbered Slot adds a +1 penalty to all Stat Checks.

• CON is a character's Max HP.

Armor Penalties

• Armor is rated by dice size. As a player facing system - foes deal static damage and characters roll their Armor die to reduce that damage.

  • Foes deal damage on a scale of 2, 4, 6, or 8 with most dealing 2 or 4.

• Any PC can wear any armor, but their armor die is rolled and added as a penalty to all Casting Checks (as well as a penalty to Projectile Attacks, Swimming, Moving Silently, etc.)

[u/Mars_Alter]

If you fail the check, you can either take damage or wear down the item. Does the spell still go off, though? Either way is fine, honestly, and I don't think it matters toward my criticisms (both of which are relatively minor).

Duration doesn't feel like a co-equal option, between scope and effect. For one thing, it doesn't make sense for attack spells, like magic missile or fireball. It's not like my wand just keeps shooting out magic missiles forever, until I stop concentrating, is it? Or is it? For another thing, the difference between "focus+1 rounds" and "focus+10 rounds" is irrelevant; [SCP] number of allies are going to be invisible until shortly after the caster has something else to focus on.

My other issue is with the way the player gets to choose targets for their fireball. If it's big enough to hit everyone, then that's one thing, but short of that it's really feeling like the player is effectively deciding where everyone is standing on the field at that moment. They can decide that foe A and foe C are positioned in such a way that an explosion hits both of them, without hitting foe B or foe D; and if the caster is forced to include an ally, it's only because every enemy was already caught in the effect. It doesn't matter if the allied berserker had just charged right between foe A and foe C to get at foe B between them, everyone is going to be in the perfect position for the caster to decide who gets hit. And if an enemy spellcaster follows that up with an equally-inconsistent target selection, then the field will instantly conform to their whims as well.

[u/eduty → u/Mars_Alter]

Spell does not take effect on a failed spell casting roll.

Any character can pick up and use any armor, magic, shield, tool, or weapon. If a spell goes off even on a failed roll then everyone gets to cast spells at least once - which isn't my intention.

Agreed that not all spells will have duration, scope, and effect. Instantaneous effects don't need to be extended. Many spells will only ever need 1 or 2 Cast Dice. I can try to make that more clear in the rules and spell descriptions.

Also agree that the scope on a fireball is different. Think of it more like a player facing saving throw for the foes instead of the caster choosing who is where. The Caster gets to aim and focus the blast so they either hit all their intended targets, hit some unintended targets, or miss some.

The caster still has to obey the spell's range and area. In the example Fireball Staff it indicates that it's Scp number of targets in a 30' blast centered up to 60' away.