Hey, for any programming experts, I was wondering if there was an ACS command (or function) that calculates the hitdice of a projectile. Say, you have a one-sided linedef out in the open, and when a projectile crosses it, it calculates how much damage it will cause if it strikes an enemy behind it. If one doesn't exist yet, how can I make one myself? Thanks.

To do this you would need to use GetActorProperty which is not yet implemented in Vavoom.

Just a curious question, is the hitdice of a projectile predetermined when it's spawned, or is it given its value when it hits a sprite?

When it hits.

Does it get a hitdice value regardless of what it hits? Say, between hitting an active Korax and hitting a one-sided linedef.

It only damages killable objects, there are checks for just exploding against decors and walls.