Skeleton iron sword is rank 19. which means it over power so it becomes the base. When ever a compound used in junior or superior has a higher rank, no matter where its placed in the equation, it will become the base.

So sorry to say this but this compound is right.

Also, sorry Thorn Gavel cannot be compounded. i'm unsure how that poster came to obtain one... he may be one of the many posters who just post for show. or perhaps they are from the gift packs.