it's the second one. The way that it's actually typically phrased in a spell description is "half as much damage". That means half of the damage that was previously specified. No dice are mentioned. Damage is defined in the Rules Glossary like this:
Damage
Damage represents harm that causes a creature or an object to lose Hit Points.
Whatever that damage is -- calculate half of that.
Yea you roll as normal and then halve it at damage resolution (individually), means you use the same procedure in all cases. Things like having a single damage dice or multiple targets that doesn't all save/fail for example would be difficult to resolve otherwise.
You can even get in situations where you need to half it twice, imagine that an infernal tiefling makes the save vs fireball. First you roll the damage then the tiefling reduces the damage in half for the save before halfing it again due to fire resistance. As such the teifling takes 1/4 of the total rolled damage.
On the flip side some features might add damage to a spell, an evoker wizard might add their INT modifier to the damage which isn't even a dice rolled. So you always roll all dice and half that total.
As others have said, you roll all the dice and the target takes half of the damage rolled. Reason for it working this way is simple - if you rolled half the dice, then spells that use an odd number of dice (like Shatter which does 3d8) would have their half damage numbers skewed one way or the other (depending on if you rounded the number of dice up or down).
So your opponent makes his save for half damage. Roll half as many damage dice? Or roll all damage dice and take half of that roll? 🤔
The latter.
Consider fireball, where you roll damage once for a group, who save or fail individually.
it's the second one. The way that it's actually typically phrased in a spell description is "half as much damage". That means half of the damage that was previously specified. No dice are mentioned. Damage is defined in the Rules Glossary like this:
Whatever that damage is -- calculate half of that.
Yea you roll as normal and then halve it at damage resolution (individually), means you use the same procedure in all cases. Things like having a single damage dice or multiple targets that doesn't all save/fail for example would be difficult to resolve otherwise.
You can even get in situations where you need to half it twice, imagine that an infernal tiefling makes the save vs fireball. First you roll the damage then the tiefling reduces the damage in half for the save before halfing it again due to fire resistance. As such the teifling takes 1/4 of the total rolled damage.
On the flip side some features might add damage to a spell, an evoker wizard might add their INT modifier to the damage which isn't even a dice rolled. So you always roll all dice and half that total.
As others have said, you roll all the dice and the target takes half of the damage rolled. Reason for it working this way is simple - if you rolled half the dice, then spells that use an odd number of dice (like Shatter which does 3d8) would have their half damage numbers skewed one way or the other (depending on if you rounded the number of dice up or down).
Thanx. Yes the odd number damage dice made me wonder. But felt I should clarify.