X, but it can proc multiple times in a row. If I cast fire I and it procced, which my computer will not register right away due to latency between the server and my location, then I will be in the middle of casting a second fire I. If that second fire I lands and procs it again, I've effectively lost the first firestarter proc. My suggestion is to create a safety net so that the black mage doesn't lose any firestarter procs that happen to get triggered back to back. My second suggestion is just to do the same thing for when a firestarter procced and he is in the middle of casting blizzard III.