emergency spell casting

Homebrew: Emergency Spell Casting

Consumables in Dungeons and Dragons are a bit iffy when it comes to their rules. In 5th Edition crafting is all but absent from the game and the rarity system is bad if you want crafting to be a mainstay of your game. Despite these rules being bad for crafters, they do shed some light on interesting mechanics when it comes to spell scrolls. These interesting features of spell scrolls as consumables lead the way when it comes to making fun emergency spell casting homebrew rules for your Wizards.

Spell Scrolls: How Do They Work?

Spell scrolls are detailed in the Dungeon Master’s Guide on page 139. As a quick summary, they are spells that are written onto a scroll where anyone who can read them can attempt to activate them. In addition to this, they are also single use. Once activated, the scroll destroys itself.

A few pages later in the DMG on page 141 we come across the rules for spells in magic items. The notable piece of information we are pulling up here is that spells in magical items do not use spell slots to cast, require no components, and are automatically cast at the spell’s lowest level. All of these are true unless the magical item states otherwise. Now we’re getting somewhere.

Are Spellbooks Magic Items?

We are about to look at stretching the rules a bit in their interpretation. For information on spell books we need to hop over to the Player’s Handbook and take a look at the scarce few paragraphs on page 114. A wizard’s spell book contains spells of 1st level or higher and wizards may transcribe spells that they find into their spell book for 50 gp and 2 hours of time per spell level. While it is true that wizards get new spell slots when they level up, the way spell books are presented suggests that a wizard could know every wizard spell and have a spell book with spells they simply cannot cast yet.

Where this gets interesting is asking if a spell book is a magical item?

What is the difference between a page in a spell book and a spell scroll?

Depending on your interpretation, we’d like to suggest a new homebrew rule: Emergency Spell Casting.

Emergency Spell Casting Rules

Let’s say your party is on the ropes. A majority of them are down and your wizard is out of spell slots. The party would need a miracle to get out of this situation alive. Your wizard’s turn comes up and they need to think fast. So what do they do? They rip a page out of their spell book and cast it like a spell scroll.

This of course destroys the spell. The wizard loses that page and the information and they’ll have to relearn it or transcribe it again. But the party will live to fight another day because the wizard decided to make a sacrifice from their precious spell book.

The core premise of this homebrew rule assumes that there are no differences between a spell in a spell book and a spell scroll. So essentially every wizard is walking around with a stack of spell scrolls they can use at will. They follow normal magic item rules. If the wizard has copied a spell into their spell book that is over their casting level, they have to use a spellcasting ability check to see if they can use it as a spell scroll.

What’s great about this as a homebrew rule is that it is self-balancing. The spells are hard to find, there is a clear cost associated with their acquisition and a fairly steep price associated with their use. Spell scrolls that are copied into a spell book are destroyed anyway, so a player would have trouble duplicating or amassing a high number of extra spell casts anyway.

Stretching Things a Bit Further: The Spell Grenade

Now we’ve come to the absolute limit here of stretching the rules: if the spell book itself is a magical item, what’s to stop a wizard from activating the whole thing at once?

Clearly this is not really keeping in line with the rules, as a spell scroll is read or activated through understanding. But in the case of a spell book that a wizard has made themselves, you could argue they understand precisely how each spell is constructed.

Let’s go back to our example from earlier. The whole party is down except the wizard and they’re unlikely to survive. This time the wizard knows there is no escape and capture is unlikely, but they’re not going down without a fight. The wizard’s turn comes up and they activate their spell book. Every spell they have copied into it casts at its lowest level, simultaneously, targeting the spell book itself. 

What does this look like?

Well, that depends on the wizard’s spells. It also depends how you would interpret so many spells going off in a single place at once considering the action limit on a single turn. The spell book will be destroyed, but a serious amount of AOE damage may also be cast.

But you get an opportunity as a DM to decide how all these spells would mix together, and even though this might be the end of your group, you’ll have an amazing final scene to describe as a flurry of spells consumes the area before the scene fades to black.

All in all this could be a fun yet extremely overpowered emergency homebrew rule.

Imagine if an enemy spell caster tried it…

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