CHIME NOISES INTENSIFY
The only aspect of the fourth I liked was multiplayer. I'm not sure why that only existed in that one.
As for the first three, I have those on PC. My favorite is the third (so fun) but the second and first are good too.
Flipendo is so dumb, but I liked come of the other spells they created (glacius, carpe retractum, spongify, lapafors, draconifors or whatever it's called)
Oh spongify. :D