Is there a general rule for which saving throws you can repeat?

Question

Some abilities mention that hit targets may repeat a saving throw against a lasting effect to "shake it off". For example Command Undead:

If it fails the saving throw and has an Intelligence of 12 or higher, it can repeat the saving throw at the end of every hour until it succeeds and breaks free.

Others don't (for example, Channel Divinity: Turn Undead).

Are there general rules for which spells/conditions/abilities allow you to repeat their saving throws, or can you only repeat a saving throw if the condition/spell/ability explicitly says so?

I ask because I saw two spells which caused the target to be frightened. One mentioned that the target may repeat its saving throws the other didn't. It seems like a huge difference, but that may be because one of those spells is of a much higher level.

For another example, if you look at the Oath of Vengeance (PHB p. 88) you see that the Paladin's Avenging Angel and Channel Divinity - Abjure Enemy abilities each have a duration of 1 minute (or damage) and no repeating saving throws. Meanwhile almost every monster ability that can cause fear allows repeating saving throws. This makes it look like a mighty dragon is not as frightening to PCs as a paladin is to a pack of undead.

Answer 1

No, there is no general rule that states that you may make additional saving throws to shake off ongoing effects. Either the spell description, or the description for the specific conditions it applies, will specify if you have the opportunity to make further saving throws against the effect. Otherwise, assume it lasts for the duration.

Many particularly incapacitating spells will feature this, but it is always explicit, not implied.

Answer 2

For the most part in D&D of the last 3 versions (3.x, 4 and 5) it usually comes down to if the spell would completely incapacitate a creature and allow for really unfair advantages during the effect.

Example: in 5e Hold Person would allow for automatic crits within 5ft so if you were simply held for the duration without a chance of coming out of it you would have upset players. I call it the Goose and Gander argument, since if the PCs can do it so can the monsters/NPCs.

On the other side 5e Banishment doesn't allow for attacks against the affected creature so no such repeating save is called for.

Hope this helps.

Read your OP as asking, in part, as maybe a template for homebrew spells as well.

Answer 3

Saving throws may only be made when a spell or effect says that they may be made. If an effect gives one opportunity for a save and the save is failed, the effect lasts for the duration or until it is removed by some other means. The target does not ever get additional saves unless explicitly stated (or if some other class or racial feature grants additional rolls -- such as a halfling's Lucky trait).