How to encourage casters to expend spellslots?

Question

As you walk in the forest, you notice a group of gnomes, tightly packed together; your turn Mr Sorcerer. "I cast Firebolt" "You mean Fireball?" "Nah, saving it for later". Ten rounds later and with 10hp left the battle is over.

It doesn't matter if it's the first battle or one after 2 hours (and no rests) of playing; burning spell slots feels risky, leaves you powerless, and you're already thinking "what if I need this later". It's not really a player-specific issue; I feel the same most of the time, and, role-playing aside, it's really hard to stop hoarding spell slots.

While there isn't a lot to be done as a player (besides picking a warlock over a wizard), there must be a way to resolve this as a GM. Some thoughts:

1. Warlock on steroids: instead of starting with, say 10 slots, you start with 5 and after each encounter you have a 50% chance to restore a used spell slot. Pros: good motivation; cons: hard to balance

2. Divination spells: the caster can use divinations to determine when the "hour of greatest need" will be. Pros: makes sense in-universe, casters would have developed this sort of thing - also feels somewhat balanced; Cons: sounds like a lame minigame: burn a spellslot and I'll tell you when to go nova

3. Narrative clues: "you see a big tall figure with skull-decorated armour and a huge dragon as a pet". Pros: seamless (?); Cons: might be too subtle or over the top

Bit surprised this hasn't been asked before tbh (but maybe my investigation score is abysmal).

Answer 1

Spell slots are only one resource ...

... and D&D is a game of resource management.

By choosing not to expend spell slots, the party is choosing to spend a different resource instead - probably hit points.

If the encounter with the gnomes leaves them low on hp then the next encounter will require them to use a different resource ... or die. Or, depending on circumstances, they may take a short rest to replenish those hp, however, short rests and hit dice are just another resource. So are the cleric's spell slots used on Cure spells. Or one use or limited use magic items.

The wizard knows they have the option of using a spell slot and choosing not to "just in case" is a perfectly valid strategy. That's their call and a DM should let them make it.

It might help if you explain this way of thinking about it to your players.

Answer 2

Create situations where spells are needed.

I'm going to slightly challenge you here: instead of upping the difficulty by damage or CR, you should create situations where casting a specific spell is far more useful than simply dealing damage.

As someone who plays a lot of caster PCs, I have two categories of spells: situation-specific ones, and bread-and-butter damage dealers. If all I need is damage, I'll stick with my cantrips and direct damage dealers, but if I need something specific, then I'll start using my other slots. At the end of one campaign, I found that I simply never used some of the spells I took, because there was never a situation where it was warranted.

However, if I'm faced with a situation where a specific spell could be useful, then I'll pick that one. For example, against a single enemy, I'd pick fire bolt because my teammates can also contribute pure damage, and I don't need to waste precious spell slots. However, if a ton of enemies were pouring through a small gap, I'd consider casting something like wall of stone.

On a related note, this is why healing in combat is so useless in 5e: healing costs your action (or bonus action), and doesn't contribute any damage to the encounter. You're almost always better off trying to deal more damage instead.

This strategy means that you need to create obvious, specific spaces in the encounter to use high-level spells. Maybe there is an area that has reversed gravity, and requires the Reverse Gravity spell to restore it to navigable conditions for the party. Maybe there's some creature that's immune to the party's damage, and it can be contained with a Forcecage. Maybe there's a puzzle that requires Telekinesis to resolve. Maybe there's a creature that's obviously vulnerable to cone of cold.

The key is to make it obvious that casting this spell will make a big difference. Your players, if they are smart, will love this--I certainly loved it when I realized that I could use one of my carefully-chosen spells to really make a difference on the battlefield instead of simply being another glass cannon.

Know which spells your players have

Obviously, in order to create encounters that invite spellcasting, you have to know what spells your casters have chosen. In our game, the DM can see all of our (online) character sheets and tailors the encounters to our items, spells, and abilities. While one could argue that this is a bit of railroading, I think it results in a much better play experience overall, because we actually get to use our abilities.

It's also important to know your players' styles. Some players (like me) will enjoy finding a "solution" to encounters that make them trivial or at least a lot easier, whereas others might resent the caster stealing the spotlight or being forced to pay a spell slot tax. It will take some trial and error to find a groove where both you and your players are happy with the usefulness of spellcasting in your game.

Answer 3

(I have never encountered this problem, but I think we can approach it as any tactical mistake the players make)

Why would they change, if they win anyway?

A Fire Bolt has less than half the damage of Fireball on level 5 even if you only consider a single target. If they win with only cantrips, you do not challange them nearly enough

Be ruthless, but merciful and obvious

Create encounters, where they will clearly lose without spending slots. Make them so that they can win even if they realize it later, and start spending spell slots.

Example

A bunch of archers close enough that the melee types can reach them in 2 rounds, but strong enough that they down one of the party members. If the party still does not realize this is the right time for a Fireball, don't be afraid ot leave a semi-permanent mark, like killing a few members (if they can be resurrected), or taken into slavery.

Answer 4

A few possible options to address this issue, depending on the player, the group, and the situation.

First, address the fear. For most players, the reason they avoid burning spell slots is because they worry that later on, they will find themselves in a situation where they desperately need spell slots and run out. This will naturally abate as players level up and get more spell slots so they can afford to hold a few in reserve, but there are other ways to help this. One of my favorites is magic items. For example, you could give the spellcaster a consumable magic item where they break a tablet to re-gain a spent spell slot, or something along those lines. This will help them know they have a backup in case of dire need, so they'll feel more comfortable using what they have.

Another is to provide direct cues. In some groups, this could include things like "it looks like you're facing the bulk of the goblin party" or "as you reach the end of the cave, you come across the final group of enemies". The goal here is to make it clear to players that they're safe blowing spell slots at this fight, as there won't be another larger fight following it. I actually DM'd one group where they appreciated direct meta knowledge - it got to the point that based on player feedback I'd just tell them "this is the big fight". I wouldn't do that for my other groups, but this group requested and appreciated it - maybe yours would too.

You can also have an experienced player help them (or talk to them yourself). In my experience, all players struggle with this but it tends to be much worse with newer players. If I have a more experienced player in the group, I've had good experiences with having the older player talk to the newer player or help suggest when to use spells. I've also done okay with suggesting it before or after a session ("Hey, I've noticed that at the end of the session you still had a bunch of spell slots left - you might think about using them more in fights, like when you were fighting those gerblins."). It's usually not as good to suggest it mid-session - when the DM tells you to do something mid-fight, you kinda feel like you have to.

You can force players to adapt or die. You can keep throwing more and more difficult fights at them where if they use their spells they'll do fine, but it will be very hard or impossible if they don't. This strongly depends on your group's type and dynamic. Some players take defeats / hard fights as a challenge to ramp up their skills. This tactic will work well for them. Others are demoralized and no longer have fun when they lose - you should avoid this tactic with them.

Finally, at the end of the day you can tune fights down. I once DM'd a group where one player's girlfriend started playing with us. However, though she played a sorcerer she never really used effective damage spells. I tried to help her out and had another experienced player try to help her, but we didn't really see any change. It wasn't an issue with expectations (thinking it's a minor fight when it wasn't), because the rest of the party managed resources well. At the end of the day, I just had to accept that she was unwilling/unable to learn how/when to use damage spells effectively, or had a different vision for her character. I tuned my fights to assume that she wouldn't ever use AoE spells and would mostly spam firebolt - once I did that, we went back to having fights at a challenging but fun level of difficulty. You just have to accept that for whatever reason some players just aren't going to play their character to its potential. Your choice at that point is to either constantly have them barely scraping by, or to tune fights down to a level they can handle.

Answer 5

I actually had this problem when I played World of Warcraft. In a minor pvp engagement, I opted not to use a cooldown. We ended up doing fine, but someone (who everyone respected) asked me why I opted to not use my cooldown, as we could have lost the engagement. I said I wanted to make sure I had it when we needed it and not waste it on an engagement where we didn't need it. I'll never forget what he told me:

If you never use it, you've already wasted it.

Now this is not something you, as a DM, need to tell them - this is something that you as a friend and mentor need to tell them. Obviously as a DM you can create situations which force them to do it, but they aren't really choosing to do it, you're forcing them to. If you really want them to learn, you have to convince them to do it.

At the end of the day (or whenever it is that they reset their slots) they should have none. Occasionally, they should run out in a battle when they need it. Occasionally, they should have an extra. But mostly, they should have none. If they're ending the day with slots, it's too easy for them and they aren't truly progressing. Where is the reward without risk?!

Answer 6

Create Multiple Difficult Encounters

I don't think this problem really needs a mechanical fix. All that really needs to happen is that your players need to learn that spell slots do not need endlessly to be conserved. The way to do that is to make them see that the best (and perhaps only) way of winning the current encounter is to blow a spell slot on it. Particularly at lower levels, spells tend to almost entirely deal with an encounter. Take sleep for example: this can often remove every monster from an encounter.

After several difficult encounters, the characters are likely to be low on hit points, and out of healing resources. It is at this point that they are probably most likely to decide that this encounter needs to be dealt with now.

Essentially, this is not a problem that needs to be dealt with by changing the rules, it can easily be dispensed with by using the rules.

If nothing is working (and your characters are miraculously still alive), try pointing out to your players at the end of the session, or when they take a long rest, that they have unspent (call them 'wasted') spell slots left over.

Answer 7

I have yet to play 5e, but this seems like an issue with vancian magic in general.

Make the players figure it out, as a group

If you have somewhat experienced players, than that type of resource management is up to them. Even if your wizard is inexperienced, if you have an experienced player at the table, it is probably better to let the experienced player provide advice than have the GM jump in with advice, much less rules changes to encourage the use of spells. Resource management is part of the game.

Now, if all of your players are new to the game and you aren't, then it might not hurt to occasionally give blatant advice as to what will work best for them. But even then, I would mage it general advice ("You are hoarding your spells too much") rather than specific ("You should use spell X now...) and still leave the call to them.

Telegraph a bit more how you view a specific encounter

This is in essence your third option, but lightly rephrased. Provide hints as to how you view an encounter to fit into the adventure, and specifically how hard you intend it to be and how many more encounters you expect after it before they can refresh. As a player I will approach what I think is a "boss fight" differently from one more small fight along the way. I will also approach what I think is the last encounter of the adventuring day differently from what I think is one in a series before I can do things like replenish spells.

How direct you should be depends on your group dynamics and your group's experience. For an experienced group that knows you well, it shouldn't take much at all for them to have a good guess at the rhythm of the session and threat level they are facing, subtle narrative description should be ample. For a brand new group you might want to drop some not so subtle hints about your intentions or if they are inexperienced and tolerate meta-gaming, even tell them bluntly "This is a boss fight".

Answer 8

You might like this question which deals with the related problem of spellcasters being too aggressive at using their spells.

Let me talk a bit more about the "spellcasters are too aggressive" problem. In D&D, sometimes it occurs that the party is only getting one encounter per day. (Perhaps because the DM hasn't put the party on a strict deadline.) Once the spellcasters realize this is happening, they will start using all their spells in that one encounter. Then, if the fighters start to advocate for doing a second battle, the spellcasters will say "no, we can't fight any more, I'm out of spells", which makes the one-battle-per-day problem worse.

When this sort of thing is happening, spellcasters will seem much more powerful than comparably leveled fighters.

It sounds like your group is having too many combats per day, so that the spellcaster needs to hoard spells aggressively. Try having fewer battles per day. Try telegraphing clearly how many battles remain in the day, so that spellcasters can plan ahead.

Also, as your group gains levels, your spellcasters will have more spell slots available, and they won't need to hoard quite as aggressively.

Answer 9

Set expectations and telegraph events

Forewarned is prepared, after all. If you want optimal resource use (including spells) you need to let the players know some of what is going to happen. The quest giver can also provide background detail; useful detail might include a description of the lair/hideout, gossip can tell you about monster sightings (farmers at the market talking about some strange shambling mound) as well as possible affiliations (a group of 20 goblins were asking for employment but were shooed away from the town), locals can tell you about the layout of nearby caves and visitors to a house can tell you about the floor layout.

Two things to keep in mind:

1. It is fun to have adventures seek out information, but until they start to think this way make the information very easy to find. Maybe as an experiment give them everything they need up front.
2. Just because you know what is coming does not mean the party will handle it with finesse; think of it as establishing a sort of riddle. You can generally increase the DC because the players will be able to plan their encounter, but still what is obvious to you might not be so obvious to the players. In time they will get a feel for how you do things but give it time.

If you are training them in this way, don't have any serious setbacks! Many players will listen at a door, if there is something unexpected that will change their established plan let them know. Having them update their plan is okay but being unfair is not; this is because if planning does not help them any more than doing things randomly then they will do things randomly. If they start to plan, then let them succeed (I mean the quest design allows for a straight forward solution - I don't mean pull punches). Then you can start throwing in variations which require them to change their plan as they go along, which as they gain levels they will have more wiggle room to do.

Beware Random encounters I have events that look like random encounters but I document all of them (in advance), and they either provide additional context (a group of travelers (actually thieves) which might try to steal from you but can also provide information), to the "oh that monster the town people were gossiping about, we found it!"

The point is: Plot and story progression are important. If you have a lot of randomness, resource management isn't possible and I like there to be a story. What does throwing a few random monsters in really add? What it does in a certain way is underscore the need to be conservative; an encounter, at least a totally random one steals time away from the story you are developing.

Consider the alternative: charting an unknown cave expanse where for whatever reasons they have to sleep in unsafe locations. This too is fun but has a completely different feel from being able to be prepared (which is how I like my adventures to be most of the time). If your players can survive an encounter, should they throw away their trump cards? The unknown should be scary, what if they get attacked at night? If the fight isn't going to kill them they should keep that nuke until the last moment and save their healing until you need to get a player back up.

The down side for the DM is that for the players to be able to plan you the DM must plan your adventures to a higher degree than is required for a simple hack-and-slash. But personally this; as a DM, is where the real fun is.

Answer 10

I always preferred the concept of mana points that recharge slowly during the day or quickly during rest, similar to what you might have in a PC game.

It's entirely possible to modify your game to convert mage and priest spells to use the psionics mana rules by giving certain spell levels a certain mana cost (maybe [spell level]^2), and then grant the spell caster a number of mana points based on their level and the number of spells you want to let them cast per day. Maybe let them use HP when mana runs out if you want to add flexibility and drama.

You aren't really playing 5e at that point, but the point is to make the game fun. The reason I think this approach could work with your player who doesn't want to use the fireball is that with a mana mechanic the player is not precluded from casting another fireball later if they need - flexibility is increased, making the game more fun. Maybe one day the player casts 2 fireballs and that's it, and then the next day they cast detect traps a few times for a similar mana expenditure (and then maybe they knock themselves unconscious by casting fireball when they had no mana left and needed to be carried).

The downside of this approach is a little more maintenance during the game to track mana points vs spell slots, especially if you let mana replenish by the hour.

Answer 11

Offer the players a carrot

While a lot of these options are based around negative reinforcement, don't forget the power of positive reinforcement too. Give the players a chance to be cool if they use their spell, then lean into the result to reinforce that popping their best spells gets them the best results.

Take the example of the wizard who uses Firebolt all day long instead of ever using Fireball. One good way to encourage it is to unveil a golden opportunity for the spell to be used, like having a pack of kobolds ambush the party by raining molotov cocktails down on them. Emphasise the way they're hiding behind makeshift palisades and grabbing the bottles out from behind them, then when the wizard hurls a fireball at them emphasise the way the whole ambush goes up in flames, kobolds and burning splinters flying in every direction.

You don't have to do it all the time, but if you start encouraging the players and getting it into their heads that spending resources is fun then it'll turn into something they'll do just because.

Rapidly restock player resources

At least for a little while. This one I experienced as a player and it did a fantastic job of getting everyone into the swing of letting fly. Give the players a few sessions just restocking their resources more frequently than normal. They're adventuring in the holy month of the god of magic and their spells recover quickly, their benefactor makes a point of checking if everyone's got a healing potion and handing them out if anyone's short, that sort of thing. Heck, even just a metagame 'hey so for a few sessions/adventures all your resources will come back frequently so you can try out your powers' with no in-game justification does the trick.

They'll be a little bit cautious at first, but soon enough the realisation will set in that hey, they're wasting the free spells and healing potions and they'll start using their abilities more. As a bonus, with more room to experiment they'll get a better handle on when the best time is to fire off those spells they've been holding in their back pocket so when the time comes they'll actually use them.

Once they're in the habit you can start dialing back again to a more moderate amount of resources, but by then you'll have worked the players out of 'famine' mode and so long as they don't feel like they have to be miserly about their resources they'll be freer with their powers.