Different spell energy types

This article is all about the different spell energy types I’m thinking of adding to my game and it was born from a conversation I started on The Temple of the Roguelike forums, where I stated that I was planning on using:

  • Mana
  • Health
  • Ally sacrifice

But was thinking of swapping these methods for:

  • Mental Fatigue
  • Spell cool downs

…and I asked if anyone had any other ideas?

I got several great responses ranging from “great idea about ally sacrifice” to “have you seen what my game does” and many more. The most interesting of these responses were those that provided actual alternative ideas that I could explore.

I thanked everyone for responding and went away with an action to examine those alternatives that I thought had some merit.

After a couple of days I’d managed to take each of the alternatives plus my original ideas and expand on them enough so I could see how they would fit into my game. I even went as far as assigning each of the major playable classes to one of these alternatives!

Below are my thoughts on each of those methods.


Using mana is a well-known and trusted way of controlling when the player character can cast spells and it is quite simple to implement.


Using the casters health to cast magic is a lesser used alternative to using mana and presents a direct risk to the caster, because low health means a greater chance of death.

To counter this the caster should be provided with cheap and quick ways to increase their  health e.g. a spell that will swap mana for health.

Ally sacrifice

Ally sacrifice is a mechanic that allows the caster to sacrifice any number of his/her allies to provide the power to cast any number of spells.

The basic idea is that the death of each ally makes available an amount of “power” that can be passed back to the caster which can then be used to cast one or more spells.

By using this mechanic not only will the casters allies attack all enemies of the caster but upon their death they will return an amount of power back to the caster, which allows the caster then to cast further spells. An interesting side thought is that the power returned to the caster could be based on how many enemies each ally has killed.

A different approach would be to get the caster to perform the sacrifice himself through the use of a sacrificial knife/sword/axe or even a spell(?).

Maybe I should allow the caster to choose how his/her ally will die?

The core gaming issue I want to avoid is the caster having no power to cast any spells thus rendering him useless and vulnerable.

One approach to resolve this would be to give them a spell that has a zero energy cost but allows them to cast a level 1 ally that will return a small amount power.

With the ally sacrifice mechanic there is the question of how long does the returned power remain with the caster? The first idea that springs to mind revolves around the level of the ally that cast the power, the greater the level the longer the power remains. But that would require management of each unit of returned power and could get quite tricky.

Another simpler mechanic could be that the caster loses power every turn and only through killing can he/she hope to keep the power levels rising. This could be supported through other spells that suspend the power levels reducing for a period of time.

Probably the most tricky question that relates to all of the different energy types for spell casting and not just ally sacrifice is how much meta-energy will be required to cast a spell.

One option is that the cost of the spell is based on its current tier plus modification based on the primary stat for casting of the caster (higher stat values mean less cost to cast)

Another option could be to have fixed costs for each spell, although I don’t really like this idea as a designer – it is still an idea that has to be considered.

To make this work, from a technical viewpoint, allies will need to be graded and/or grouped together so they can provide roughly the same amount of power back to the caster. My immediate thoughts on solving this issue is to use the race of each ally as the basis and then work up from there.

Spells have charges

Simply put this means that a spell can be cast a specific number of times without the need for any further preparation, ingredients or penalties to the caster (unless the spell fails).

One of the key questions for this mechanic is how can the spells be prepared?

I can think of using rituals, ingredients and over time as valid options.

Over time seems simple and easy to implement; A possible method could be that once the spell has been exhausted the game creates a delayed effect that when it expires adds a charge to the spell. This effect could be replicated to allow for multiple charges added to the spell over time. Further gaming options could be to have all the charges re-applied after x turns or to have each charge re-applied after x turns. I’m sure my code design could allow for both methods quite easily.

Ingredients could apply to any physical item or items and require a specific action to combine the ingredients before the spell can be recharged. Thinking a little more it could allow for a scarcity mini-game where the caster has to go hunting for the ingredients to allow him/her to cast spells…which may lead them into further danger as they progress into areas of the dungeon they aren’t prepared for.

Rituals would require a distinct action by the player character to prepare and then complete the ritual (maybe that’s two actions?) which would then take a number of turns before the spell is fully recharged and maybe spells couldn’t be partly recharged if the ritual is interrupted. A question or two arises about the actual rituals themselves such as where can they take place and do they need specific materials to be successful (sub thought: can critical items be used to increase the maximum number of charges for that spell, e.g. from 3 to 4 charges?)

So how many charges should each spell have, the first thing that sprang into my mind is having the number of charges is based on the spell current tier id; The lower the tier the more charges it gains which allows for the perception that the higher tier id of the spell the more powerful it is.

Or should all spells have the same number of charges – simple, boring but very easy to implement.

Another question that comes to my mind is how many spells can hold a charge at any one time? Essentially this is a control against the player who wants to just “blast away with everything” – and that’s not what my game is principally about.

What comes to mind is using the primary casting stat (of the caster) to control how many spells can hold a charge at any one time. Sprinkled with a chance of increasing that number through some spell buff and/or bonus.

Using a totem pole (aka a fetish)

Once the totem pole has been placed on the ground it emits an energy field that provides the caster (or even everyone in that field) with enough energy to cast spells.

The totem pole would last for so many turns before it is exhausted at which point it should be collected by the caster and allowed to recharge over time and of course whilst it is recharging the caster cannot cast spells – quite an interesting challenge for the player I think.

How many turns the totem pole provides energy for is just as important as how long does it take for the totem pole to recharge. There are two ways, that I can see, I could/should use the primary spell casting stat of the caster to provide the (initial) energy and how about using the highest tier id of any spell cast to control the recharge duration, maybe not as pure numbers but certainly the primary input for calculations.

Different totem poles could/will provide different energy and recharge rates.

Mental Fatigue

Mental fatigue represents the amount of concentration needed to cast spells, each spell produces fatigue that the caster accumulates over time and therefore makes it slightly more difficult to cast the next spell. If he/she stops casting spells then this fatigue will go down, however if he continues to cast spells then the increase in mental fatigue will affect his physical statues, e.g. they could pass out thus rendering themselves vulnerable to attack and maybe death.

As mentioned each spell causes mental fatigue and I think that the higher the tier id of the spell the more mental fatigue is generated. As a general principle this is great but I would want the willpower of the caster to be used to determine the actual amount of fatigue the caster gains.

As the fatigue levels increase the player will notice status changes (or penalties) to their character manifesting themselves, possibly as physical side-effects, for example the character may have their movement rate start to reduce or passing out and thus losing one or more turns.

Once the caster reaches their maximum mental fatigue level then no more spells can be cast; And it’s probably true to say the character will be unconscious and possibly die from attacks they can’t respond to.

What does the character do to reduce their fatigue levels, the most obvious one is to rest (or even sleep?) for a number of turns. Eating fresh fruit could be another option (though I don’t have fruit as a food source in my game) and maybe drinking specific potions.

Environment based energy

My initial thoughts (and I admit they are based on a forum comment) are that the terrain will contain both pockets of energy and natural energy seeping from the ground. This will allow the caster to cast spells wherever they are but if they want to cast something powerful or more than 1 spell then they need to move into these pockets.

When the caster is moving around isolated and specific terrain tiles will contain enough energy to allow the casting a single spell. The caster will need some indication of where the next “casting” terrain tile is located and I’m not sure how to do that yet, maybe a visual marker of some kind.

These pockets of “casting” terrain shouldn’t be too far apart otherwise the caster will be vulnerable and conversely they shouldn’t allow for too high a spell level to be cast – or maybe one or two per level could be placed that allow for this.

Once the caster is “on the tile” then those spells that can be cast should become active and so long as the caster stays on that tile then he can cast a spell. If he moves off of that tile without casting a spell then the energy should remain, so he can return at a later date.

The “pools of energy” should be a small group of tiles that allow the caster to cast any number and amount of spells until the energy is exhausted, upon which the “pool” is never recharged it is totally exhausted.

Each pool of energy will have a finite amount of energy that can be reduced by spells being cast from within it until it is totally exhausted.

The pools of energy are available to those magical monsters that can make use of them, e.g. the Druid class, but all magically aware monsters will know about them and know that the player (if they are of the Druid class) will make for the pool of energy.

Spell preparation

This allows the caster to have a set number of spells ready to be cast at a moment’s notice. Each spell can only be cast once before it needs preparing again. To offset this one-shot spell casting approach my thoughts are turning towards a quick turn-around for preparing spells and/or maybe only part preparing spells so they can be used quicker.

I’m almost certainly going to allow the caster to prepare all their known spells, I’m also thinking of having no cool down on the spells for this mechanic.

To prepare a spell the caster needs to be remain in the same location and uninterrupted for a number of turns, whilst he “relearns” the spell(s), what I’m not sure about is whether the use of “ingredients” will provide any benefits.

It is possible that the caster will find themselves in a situation where they have no prepared spells and I’m thinking of giving the caster a small chance of casting any spell without it being prepared. The consequences are dire and even death may occur as a result of a failed casting.

Leave a comment and tell me what you think, I’d love to hear about your thoughts.

This entry was posted in design, magic, Spellcasting, spells and tagged , , , , , , . Bookmark the permalink.