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Simplified 5e: Curating Spells
🕑 Added 2025-08-29 15:48:01 +0000 UTCNothing says "Magic!" like halting the game to spend a minute or three or ten looking up a spell and trying to figure out how it works.
Here's the sleep spell from D&D 5.5:
Sleep
Level 1 Enchantment (Bard, Sorcerer, Wizard)
Casting Time: Action
Range: 60 feet
Components: V, S, M (a pinch of sand or rose petals)
Duration: Concentration, up to 1 minute
Each creature of your choice in a 5-foot-radius Sphere centered on a point within range must succeed on a Wisdom saving throw or have the Incapacitated condition until the end of its next turn, at which point it must repeat the save. If the target fails the second save, the target has the Unconscious condition for the duration. The spell ends on a target if it takes damage or someone within 5 feet of it takes an action to shake it out of the spell’s effect.
Creatures that don’t sleep, such as elves, or that have Immunity to the Exhaustion condition automatically succeed on saves against this spell.
Seems reasonable, right? Except the spell has, hiding beneath it, a lot of rules. A lot.
If J. Random Gamer tries to cast this spell, here are the terms they need to look up to understand how exactly this spell works:
Concentration
Sphere
Incapacitated
Unconscious
We then have an immunity check that comes at the end of the spell's description.
Let's also break down all the spots where this spell could go wrong. I'm basing this list on my experience running ridiculous amounts of TTRPGs at game conventions with strangers:
Target: Each creature of your choice is forgiving, but players forget this all the time.
Sphere: Playing on a grid, players always forget if they can center it in the middle of a square or an intersection. A weird case where the grid makes things more difficult.
Incapacitated: Did you know that incapacitated creatures can still move? Everyone forgets this because it's a great example of overly fiddly rules and the frankly bad implementation of conditions in 5.5.
Second Save and Unconscious: My guess is that about 50% of groups forget this. People hate tracking stuff and usually just forget to do it.
The end condition of taking damage or waking a creature. This one is not so bad in earlier versions of sleep that explicitly call out creatures falling asleep. Players intuitively understand what that means. Good TTRPG design leans into this. This version really needs to do this because the "sleeping" guy is walking his speed. Why not just walk into a wall and end the spell before your second save?
Technically Spinal Tap could show up, crank their amps to 11, and play a set. According to this spell, that does not wake anyone up from "sleep" because it does not specify anything about loud noise.
Creatures that don't sleep - we'll get into this in monster design, but boy do I hate this. I now need to specify whether a creature sleeps or not in EVERY stat block I make for this game. That's crazy tech debt for one spell.
Magic the Gathering is known as the most complicated game in the world, yet a Magic card designed like this would end up in the bin. What would a design optimized for execution time and clarity look like? Let's try this:
Arcane Slumber
Level 1 Enchantment (Bard, Sorcerer, Wizard)
Casting Time: Action
Range: 60 feet
Components: V, S, M (a pinch of sand or rose petals)
Duration: Instantaneous
Pick a point in space within range. Living creatures with 12 or fewer hit points within 10 feet of that point must make Wisdom saving throws or fall asleep.
Where'd all the words go? This version of sleep does two things.
Looking at this spell, assume that asleep is a condition that we can look up in the rules. However, it works as we expect - you're unconscious, but are awakened if you are disturbed (loud noise, damage, touch).
Living creatures is a new keyword. Living and nonliving are tags attached to each creature type. It can also be overwritten by a local creature definition. Living includes aberrations, beasts, celestials, dragons, fey, fiends, giants, humanoids, monstrosities, and plants. Nonliving includes constructs, elementals, oozes, and undead. My highly advanced, PhD game designer brain sorted types into these categories by asking, "Would this type of creature eat a ham sandwich?"
The hit point cap focuses the spell on weaker creatures or ones that have taken a bunch of damage. Note that I specifically do not scale this spell up. It's your weapon of choice for disposing of weak minions or of handling the rowdy villagers at the local pub. Part of this is tradition (sleep was the nuclear bomb of AD&D at low levels) but it also gives this spell a unique niche in the game.
The point of this exercise isn't, "Rules bad! The game can just suggest stuff and you can figure it out!" Vibe gaming is cool, but I think we can get the best of both worlds by thinking carefully about how to present effects. Design for the reality at the table, the experience of a person who doesn't know the rules in detail but can read and do what a text says to do.
In this case, we're using a term like asleep because the common understanding of how that works can map to a robust mechanical definition. Most groups can just vibe their way through this and get it 90% right. When an argument arises, the book gives a clear, technical definition.
The fatal flaw of the 5.5 spell is that it requires a technical understanding to function. If you use vibes to resolve the spell, you are very likely making it far too powerful. You need to read a lot of rules to get this right, slowing the game and distracting us from the real business of D&D.
Even worse, the poor chap who read the spell and now has to explain it to a vibe gamer is in for a rough time. If I actually use the rules, I end up with a spell that might simply fail to function (what if an "incapacitated" creature runs into a wall? Can it bang its hand to take a point of damage and wake up?) or that has significant, annoying overhead.
With spells, I'm following a few basic design guides:
Make the vibe gamer and the person who actually reads the rules match as closely as possible.
Use keywords and condition definitions as a second tier, deep resource for resolution. The mechanic's name should, 90% of the time, duplicate its actual effect if you vibe your way through it.
If a spell develops any complexity in the interest of tuning its power, redesign to adjust its power level so it has innate or easy to understand guard rails.
Comments
Samir El Aouar
I loved how simple arcane slumber is, and the fact it works even in higher level, as you said, if the creature's hit points are reduced to 12 hp.
Mike Mearls
Good point! I was in math brain mode and thinking about a good cutoff point. It's a little lame if you roll low and the spell ends up being worthless. Maybe 2d8 + Int bonus?
Leonardo Raele
Why a fixed 12 instead of some dice (e.g. "3d10") ? Rolling dice is fun. (I think it's easier to remember too)
