# Talk:Spellbook of fireball
From what I can tell, the part about not being able to cast the spell on monsters on dark squares is wrong. I've used intrinsic and extrinsic telepathy, and detect monsters to cast fireball on monsters that are on the other side of walls.
--Turtle (talk) 22:44, 19 June 2016 (UTC)Turtle
Yes, a GruntHack "bug fix" to fireball/cone of cold allowed them to be cast at detected monsters with telepathy, monster detection or similar. This means *any* monster within 10 squares, including anything behind walls.. This affects:

NetHack 3.6.0
GruntHack
All NetHack4 variants
--FIQ (talk) 23:12, 19 June 2016 (UTC)