Stuff, for instance. Lots and lots of stuff. Lead to make lead curse tablets, for instance. The hair of the object of the spell. Not to mention nastier stuff. Which wizard characters are singularly undersupplied with in most fantasy works. Most, at most, go back to Gandalf with only his staff, and earlier perhaps, to Circe with her wand. But then, Gandalf and Circe had advantages over most folkloric magic as well as most fantasy ones; something about not being human helps.
And nastiness. Even love spells that explicitly ask for eternal love often express themselves quite vigorously about the force with which the target is to be bound. Ones that try to separate a couple or render the man impotent get worse. And if they want to punish a thief or win a competition or defend themselves at law or even just find stuff. . . . Roman formularies for lead curse tablets suggest using a cold-water pipe stolen from the water system. Not that it was difficult to get lead, but such a theft was a suitable way of starting things out.
I wonder how much of Robert E. Howard's sorcerers are based directly on such lore -- or indirectly, I suppose it could have been in the air for the pulps at that time. Certainly it smacks rather more of such lore than more recent fantasy. Down to and including having the one unambiguous white magic -- where, in "The Phoenix On The Sword", the magician puts, well, a phoenix on the sword -- being connected with religion, because the magician is also a priest.