I was introduced to OD&D in the 70s by a high school friend and his brother. During one of these games, when it was my turn, I cast a fireball. I told the DM where I wanted it centered and rolled damage. He then explained to me just how big the area of effect was, how small the cavern we were in was, and how I had managed to not only kill all the monsters but half of my own party as well, including myself.


Years later, when I had managed to save enough money, not earmarked for anything else, I went to our local gaming store to buy my own copy of the game. They didn’t have any OD&D in stock, but the Holmes edition had just come out. I’m glad it worked out that way. I took it home and immediately fell in love with it. Even today, Holmes BD&D is my favorite edition. It may be too limited for the games I want to run now, but there is a magic in those pages that makes me happy every time I pull it off the shelf.

While running a game back then, a player cast a fireball and I got to explain to him how blowback worked and how he too had not only killed all the monsters but half of his own party. Naturally, I felt a bit of nostalgia being on the other end of that conversation.

However, those two moments had one other thing in common. On the player’s turn, the wizard cast a spell and it immediately took effect. There was no delay.

1e AD&D

When first edition came out, spell descriptions included a new stat (casting time) for each spell. Typically, this was one segment per level of the spell. A segment was one tenth of a combat round. In essence, casting time was an extension of initiative, determining when in a round a spell would take effect. Higher level spells took longer to cast and therefore took effect later in the round.

1e also introduced weapon speed, which similarly determined when in a round an attack would take place. We did not like weapon speed, nor did we like casting times. They seemed (to us) to both do the same thing, one for spells the other for melee attacks. Both seemed unnecessary with no redeeming qualities.

Some spells had extremely long casting times (hours or days). Usually, those cases seemed justified and we kept them, but other than those few exceptions we completely threw out both of these new rules.

My Game

Rules for casting times, in newer editions, went through minor changes. But they essentially remained the same. Our group never really saw the benefit and never used them.

However, one day I was inspired by something 4e did. They introduced rituals. This sparked something in me. With this new concept in mind, I turned an eye back to our game. There are some spells that take a long time to cast (which we kept), while we discarded casting times in all others. There are also some spells that require expensive or rare material components (which again, we kept), while we discarded the need for components in all other spells. Rituals gave me a way to tie these differences together.

Since then, and for years now (in my game), a ritual always requires more than a single round to cast and always requires material components, while non-ritual spells are cast immediately and do not require material components. Although simply a matter of semantics, this removed the seemingly arbitrary differences between spells with different casting times and spells that did or did not require material components. By simply writing an “R” next to a spell in a spell list, it was easy to signify which spells were rituals. This was a well-received change and made life a little easier.

But, over time, I came to realize that something was still missing.

Casting Time: One Round

Maybe it was because of our background with early D&D. When we saw “Casting Time: One Round”, we all took that to mean that casting that particular spell was what newer editions refer to as a “full-round action”. In other words, we assumed that the intent was for the casting of that spell to require the caster’s full attention for the entire round. We had already thrown out casting times anyway, so our interpretation simply justified what we were doing. A wizard in our game, casting a spell, could move but not take any other action on their turn, beyond casting that spell.

The problem with this is that if the player waits for her turn, says “I’m casting fireball”, and then the spell takes effect, how does anyone attempt to counter (or interrupt) the spell? In WoW, many classes have the ability to do this. On a raid, characters are assigned the role of monitoring enemy spell casters and interrupting them as they can.

Since we had thrown out casting times, that didn’t leave any opportunity to interrupt spellcasting. It was time to rethink the way we cast spells. I wanted a simple, clear-cut method of attempting to stop an enemy caster from casting a spell.

Go back to that line in the stat block that says “Casting Time: One Round”. How long is a round? It doesn’t say the caster’s turn. It says one round. Suddenly, I had an epiphany.

My New Change

From now on, when a caster wants to cast a spell, the casting of that spell begins at the beginning of the caster’s turn and continues until the beginning of the caster’s next turn, at which time the spell takes effect. If the caster takes damage during that time, the caster needs to make a concentration check or the spell is aborted (and is lost).

Rituals take longer to cast but otherwise work the same way. Feather fall is the sole exception and casts instantly.

This gives the adventurers much more control when fighting spell-casting monsters, and makes it much more important for adventurers to use protective magics (so as not to have spells interrupted) when fighting intelligent opponents.

This Isn’t New

By now, many of you will realize that this is exactly how spell casting is supposed to work (now). In 1e and 2e, this wasn’t the case. In those editions, spells go into effect at the end of the round when spell casting began or, in the case of multi-round casting times, the end of the last round of casting. It wasn’t until 3e that a casting time of one round extended until the beginning of the caster’s turn in the following round.

I’m not sure how I feel about having an epiphany that led me to an existing rule, but at least I can take solace in the fact that it was only an existing rule in an edition that I don’t play.

However I got here, I’m pleased that I did. I enjoy the ability to interrupt enemy spell casters. It adds a certain amount of depth to combat encounters.

To those who play any pre-3e edition, and therefore (like me) didn’t use casting times and/or weren’t aware of this rule, let me say that I whole-heartedly recommend its use. It is simple to implement and well worthwhile.