Could I cast on myself the same spell limitless? could this be a good strategy for a combat?

Question

Following the Rules Compendium page 137 in the paragraph "combining spells effect" it is used an example where the same spell may be directed to the same target but the effects would not cumulate.

"Same Effect with Differing Durations: When the same effect is cast more than once on the same target, the durations of the effects don’t stack. Each effect’s duration elapses normally."

This means that the same spell could be casted on the same target or area but I can not find any mention in regards to a limit on how many times this could be done.

Therefore, could I possibly cast on myself the same spell (e.g. death ward ) 10 times before a fight if I wanted to slow it being dispelled?

Rationale: to dispell my 10 "death wards" the caster dispelling would then need to roll 10 times.

Answer 1

Correct, you can layer copies of the same spell to protect against dispelling. They don’t do anything else, that is, the is no difference between having 10 copies and having 1 copy until you get dispelled, but you can do it. There is no limit (aside from your spells per day, or at the extreme, the number of times you can successfully cast the spell before the duration of the first wears off).

This is not a sound strategy, however. You have a limited number of spells you can cast each day, and you generally want each to actually do something. Dispelling is certainly a risk worth protecting against, but it doesn’t come up constantly, so a lot of those redundant spells aren’t going to come up, making your proposal extremely wasteful.

It also isn't as good at protecting the spell effect as you might think. When dispel magic is used on a specific target, e.g. you, it attempts to dispel every spell on the target. That is by far the most common way to dispel anything. So it is not as though this approach guarantees that it will take 10 dispel magics to eliminate the effect. Forcing them to roll repeatedly does mean they are more likely to miss some, but now they are killing multiple 4th-level spells with a single casting of a 3rd-level spell.

Also, most spells don’t last all day, so you have to re-cast them. Often, you won’t have time to cast multiple copies. Or you want to use Divine Metamagic (Persist) to make them last 24 hours, but that requires 6 uses of turn undead each time, limiting how many times you can do it.

For spells which naturally last hours, it becomes more plausible.

But ultimately, there are just easier ways to protect against dispelling.

Answer 2

Rationale: to dispell my 10 "death wards" the caster dispelling would then need to roll 10 times.

That is true, but it comes with two problems:

1. You have used 10 spell slots of level 4 or higher to prevent one 3rd level spell from working. Spell that may not even happen. Probably there was a ton of other things to do with these slots.

2. You need a whole minute to prepare, and then have relatively short time it works ("Duration: 1 min./level"). So you need to be certain fight will start in the rather narrow time window, or you don't finish your preparations, or it is too late and instances of your Death Ward starts to time out and go to waste.

   Spells with longer duration would work better in that regard, of course, but that limits valid choices for your strategy pretty severely.

Thus, while there are no artificial limits to how many times you can cast Death Ward on yourself, casting it many times quickly becomes too expensive to be viable. In a niche situation when you know that Big Boss loves to dispel and cast death spells, this may be viable strategy, but most of the time, it is not.