Recently, our party barbarian gained two levels of Exhaustion. As per the rules of that condition (PHB, p. 291), the effect of level 2 Exhaustion is:
Speed halved
The fly spell (PHB, p. 243) has the following effect:
You touch a willing creature. The target gains a flying speed of 60 feet for the duration.
We wondered what the barbarian's speed would have been if fly was cast on him. Which of the above rules would be considered more specific? Would the barbarian be able to fly for 60 feet, or only 30 feet, per turn?
Best Answer
Their flying speed is 30.
These rules do not conflict, so there's no need for "specific vs. general" silliness. Fly gives you a flying speed of 60, in the same way that, say, being an elf gives you a walking speed of 30. Exhaustion then cuts it in half.
Exhaustion doesn't say whether it applies to all your movement speeds or just walking speed. However, it would be pretty bizarre to be able to swim or climb at full speed when you're so tired or starved that you can't walk at full speed.