For years, my gaming group (based on the Monty Python sketch) developed the habit of substituting "fish" in place of random nouns in describing spells and magic items. General hillarity ensued: Otto's Irresistable Fish, Cone of Fish, Fish of Sustarre, Tenser's Floating Fish, Tasha's Uncontrollable Hideous Fish, etc.
That said, I don't want to derail the thread. I'm especially taken with Wombat Tasting.
So, in the spirit of the thread, I offer:
Blame Arrow (generally only cast by mothers), Fire Crap, Remove Purse, Phantasmal Miller (nothing scarier than being attacked by a hallucination of the mean old guy who runs the nearby wheat mill), Mall of Ice (causes salespeople in enclosed shopping area to become surly and unhelpful), Acid Hog (sort of like the expression 'heroin pig' but much more screwed up), Feather Ball (Fireball's less satisfying cousin).
What if we add two letters in place of one: Nystul's Tragic Aura (generally used as a form of self-aggrandizement for under-employed artists).
One could also think of words that simply rhyme, despite spelling differences; I'm thinking, for instance, of Otto's Irresistable Pants.