Background

I created a homebrew spell, copying Acid Arrow to change to lightning damage. Damage is 3d6 with the standard cast. At higher levels, I wanted to add 2d4 instead of 1d6.

Expected Behavior

When adding the 'at higher levels' modifier, you can select the number of dice and the die type. I expected the damage for each level above the spell level to add 2d4 to the initial 3d6. Ex: cast at 3rd level ---> 3d6+2d4 Lightning damage. At 4th level ---> 3d6+4d4 Lightning damage.

Issue

When you try to upcast the spell, it adds the number of dice together and changes the die type to the one in the 'at higher levels' modifier. So casting at 3rd level leads to the damage being 5d4 Lighting. At 4th level, the damage is 7d4.

Supporting Images

Here is a copy of the modifiers section

The damage section in the following images shows the difference in die types between casting at 2nd level and 3rd level. (Ignore the unchanged section of the spell description, the damage was what I was worried about)

If you add 2 additional Modifiers, each for 0 damage, you should be able to add the d4 damage scaling to those instead of the regular base damage and it should work.

I hope that helps.

Quote from Halfwing >>

I may be wrong, but I suspect that this may be due to nothing official behaving in this manner (that I can recall, anyway!). The closest approximation that I can think of is with the spell chaos bolt, which has two separate damage rolls from the start; this may be a matter of the tools never having been built to allow for multiple die size scaling in this manner.

In that case, I’d suggest refactoring your die sizes to approximate the same amount of damage but with a different “formula” of dice for the initial and later damage.

This would probably be the best solution, however, with the way the tool is worded when entering these values, it is reasonable to presume it shouldn't happen the way it does.

If you aren't supposed to mix die types, why give us the option to select one?