dnd 5e – Uncanny Dodge and Protective Field (Or other damage reduction abilities) Order of Operations

I had a scenario come up in game this past weekend that I wasn’t sure how to adjudicate. The rogue was hit by a big hit (>30 damage) and decided to use uncanny dodge to reduce the damage, but at the same time the Psi Warrior decided to also reduce that damage using his protective field.

Which order should the abilities be applied?

  1. Uncanny dodge first, then protective field. Basic PEMDAS, we do division before subtraction.
  2. Protective field first. While uncanny dodge does not give resistance to the damage, it functions like resistance by halving the damage and as such should come after.
  3. Whichever order the rogue wants it to be in. Based on the rules for effect timings at the start of a creature’s turn, the creature being affected gets to choose the order. (Though in this case that is certainly going to be option 1 for the maximum damage reduction).