This item grants an ability to call meteors down from the sky.
It temporarily destroys wall tiles, which then respawn, similar to the tiles in the Sandworm dungeon.
Since looting this item 2 nights ago, I have experienced around 5 different situations which would have ended my playthrough due to bugs if I didn't save scum.
In particular, the Temporal Rift bosses that drop the "exits" to their levels on level 2 and 3, both got stuck under meteor rain tiles and did not spawn their portals properly. Again, if I was not smart enough to back up my saves and save scum, this would have been the end of my character after ~10 hours.
In addition, right after killing The Master in Dreadfell, I used this item on some trash mobs, hit autoexplore after killing them, and immediately died to my character "autoexploring" into a tile that was respawning, suffocating me. If I had been playing on Roguelike this would have been pretty annoying. Not that I would autoexplore much on RL, but still...
Might I recommend that this spell have the "temporary tile destruction" aspect removed... it's a great spell and does good fire damage, but it doesn't seem like it mixes well with significant portions of the game.
Again I have had this item less than 5 hours and have already had this much trouble.. I can't imagine how many actual issues there are with such an effect.