There might be a bug with the Alistair's Fundamental Breakdown spell when gifted / perk. Every time I've tried to cast it on my orcish priest of The Multitude in this run, a series of error messages show up. It seems to work okay but I haven't tested it on any creatures.
It works fine when I test orcish mages in Wizard Mode.
Would be very to reproduce, as actually getting it via perk or gifted from The Multitude is very rare.