D&D 5E Prepared vs Unprepared spells Help

[ZedSpace]

Hi, I'm still fairly new to D&D. I'm playing 5e in case there is any confusion. I know how spell casting works and I know about spell slots, but I'm still confused about Prepared vs Unprepared spells. If a spell is prepared, is the caster able to cast it without using a spell slot? Also, if a spell is unprepared, does that mean the caster must expend a spell slot?

Thanks, ZedSpace

 

[jaelis]

If a spell is prepared, you can cast it, expending a slot. If it is not prepared, then you can't cast it at all.*

Some classes don't prepare spells, they just have a list of spells known that are, effectively, always prepared.

--
*If you cast a spell as a ritual then it doesn't use a slot, and doesn't always need to be prepared; that has some special rules depending on your class.

 

[bid]

Bards "know" ~25 spells and have them all prepared. They have no access to other spells.
Wizards "know" ~50 spells in their spellbook and can prepare ~25 of those every day. They have no access to other spells.
Clerics "know" all their spells and can prepare ~25 every day.

The difference is how every "morning" you pick and choose which spells you will cast over the day:
- bards choose all the spells they know,
- wizards choose from their spellbook,
- cleric choose from their spell list.

If the cleric knows ahead of time what obstacles the party will encounter, he will be prepared to face them. The wizard maybe, if he has it in his spellbook. The bard just can't adapt.

 

[gyor]

In practice how often does the wizard or cleric knew the obstancles ahead of them besides the obvious?

The Bard and Sorceror (especially favoured soul v2) can be prepared for most things with a wise spell selection.

A healing spell if they have it, diverse choice of cantrips, a divination spell, Major Illusion, a couple of buffs, Chromatic orb, maybe one area damage spell, a good summoning spell, revivfy (you will rarely need raise dead or resurrection, if you can't get the kill person within a minute the party is likely already dead), a low level enchantment like command or suggestion. Heal. After that everything else is gravy. You won't be prepared for every situation, but the vast majority of them.

 

[BoldItalic]

It might help to think of it in concrete terms.

Suppose you have a box of spell cards (they do exist), with each card printed with the text of a different spell. You have six different cards in the box, and those are all the spells your 1st-level wizard knows. You chose the six when you created the character.

At the beginning of the adventuring day, after your wizard has taken a long rest, you pick four of those cards and lay them on the table in front of you, beside your character sheet. The other two stay in the box - you don't think you will need them today. The four cards on the table are the ones you have prepared.

Also lay on the table, beside your character sheet, two counters. Those represent your spell slots.

When you get to a point in the adventure where you think it's a good time to cast a spell, you point to one of the cards in front of you and say you are casting that spell. Then you put aside one of the spell-slot counters to pay for it, and the spell is cast. The card stays on the table - you might need to cast the same spell again later - but the counter is removed.

Obviously, you can only do that twice during the day and then you will have used up your counters. This means that there will be three or four spells that you had prepared (laid on the table) but haven't cast at all that day because it turned out that you didn't need them. That's okay; you had to guess at the beginning of the day which ones to prepare before you knew how the adventure was going to pan out.

 

[Cognomen's Cassowary]

The first thing to know about preparing spells: not every class has to do it. Some (examples: bard, sorcerer) simply know a set number of spells and can cast any of them until they run out of spell slots of the appropriate level. Others (cleric, wizard) must prepare spells.

The second thing to know: a class that has to prepare spells will select them from a larger set of spells. For a wizard, this set is recorded in a spellbook. For other classes that prepare, the larger set is any of the class spells listed in the Player's Handbook or other source books.

The third thing to know: the player decides after a long rest which spells from the larger set to prepare for the coming day.

The fourth thing to know: casting a prepared spell costs a spell slot.

The fifth thing to know: there is one exception. A spell with the ritual tag, if cast as a ritual, does not cost a spell slot.

The sixth thing to know: the character cannot cast any spell which is not prepared for the day.

The seventh thing to know: there is one exception to this as well. The wizard can cast a spell with the ritual tag, as a ritual, even if the spell is not prepared. Other classes, even if they have ritual casting, cannot do this. A spell with the ritual tag, if cast as a ritual, does not cost a spell slot, regardless of whether the spell is prepared or not.