Top Ten Most Dangerous Harry Potter Spells that are Not Unforgivable Curses

Uncontrollable flames, capable of easily killing things AND CAN EVEN DESTROY A HORCRUX

As seen in Half-Blood Prince, the spell can be considered deadly as it lacerated Malfoy leaving him extremely bloodied and dying. George Weasley also lost an ear to it.

The severing charm can actually cut humans like Sectumsempra, though it usually can do so on objects instead.

The Blasting Curse, intended target explodes if properly cast, also it is quite fiery.

The Body-bind Curse leaves the target immobile. Just imagine where and when it CAN happen and it can be considered highly dangerous.

While it's not physically harmful (unless you count Lockhart trying to use Ron's broken wand and it backfiring on him), losing your memories is very dangerous depending on where you are.

Used in the second Fantastic Beasts film, this is highly different from the other Protegos in that a fiery ring surrounds the caster.

This and Reducto are a lot like Confringo in that they blast things apart.