How do I calculate the challenge rating of monsters that feature abilities that do not directly do damage?
For example, my homebrew monster has the two following abilities:
The target takes a Constitution saving throw. On a failure, it drops to 0 hit points.
This one could be used on a character with 10 hit points, or 100, which creates drastically different damage results depending on character level.
All creatures within 60ft take a Wisdom saving throw. Each target that fails is stunned for 1 round.
This can be extremely dangerous if this monster is paired with monsters that can make use of the stun condition, but it is virtually useless if the monster is alone.
I'm sure there are infinitely more examples of this type of thing.
How do we calculate CR for monsters that do not rely on standard attacks?