Tiffany dealing with an amorous and obsessive Wintersmith.
She didn't just deal with the Wintersmith: she taught him in one stroke what it is to be human, and while he was distracted, redirected the heat of the sun to melt him and his entire palace.
Granny Weatherwax using reverse-headology to convince the other witches to give Mrs. Earwig's star pupil Miss Treason's old cottage. Annagramma, of course, screws up big time, discrediting Mrs. Earwig. Tiffany, angry at Granny using Annagramma as a dupe in her game, organizes the other apprentice witches into getting Annagramma back onto her feet. So Annagramma's doing well, but all the witches know that Granny's favorite witch-in-training had to come to her rescue, so Mrs. Earwig's still discredited.
Annagramma later gets one of her own, scaring the trousers off a group of villagers by bursting onto the scene like a mad old crone out of hell (special effects courtesy of Boffo's Novelty & Joke Shop, No. 4, Tenth Egg Street, Ankh-Morpork, "If It's A Laugh...It's A Boffo!!!"), and blasting the Wintersmith (who's in a fake human body, threatening Tiffany) with a fireball.
In this corner, Nanny Ogg's BadassLoveable Sex Maniac cat, Greebo. In this corner, Granny Weatherwax's puny little kitten, You. Poor Greebo.
Yeah, the only other animals that even slowed Greebo down before were Mrs. Gogol's cockerel Legba and a Mama Bear vixen defending her kits.
Notice how this correlates towards the relationships between witches. Mrs. Gogol and Nanny Ogg are about equal, though I would rank Nanny Ogg a bit higher. Granny Weatherwax is..., well, she's Granny Weatherwax. So, You beats Greebo, but Greebo and Legba cannot beat each other.
The Feegles convince The Ferryman to cross back without the extra payment he demanded. How? By threatening to stay.
Stop stealing the funeral meat, you wee scuggans!
Nanny Ogg just being Nanny Ogg is pretty awesome at any time.