"Protego Maxima. Fianto Duri. Repello Inimicum."
Hogwarts Castle being magically fortified[src]

Fianto Duri was the incantation of a charm that, when combined with a protective spell such as Protego Maxima, could cause magical defences to become hard or more durable.[1]


Bodies crossing the boundaries of the barrier disintegrate on the spot (which may or may not be an effect of this spell,) while spells cast at it (if not of enough power to break it) create large, resonating explosions. This spell's effect was most likely one that, when combined with the other two, bolsters the strength of the shield itself against extremely powerful spells; this was unlike minor shield spells, which only block weak jinxes, hexes and curses. Given its etymology, it was likely this spell causes a solid barrier to be made out of spells such as Protego Maxima or other protective spells.[1]

Known uses

Snatchers being disintegrated by the power of this spell combined with other protections

This spell was cast by Charms Master Filius Flitwick to protect the boundaries of Hogwarts Castle from the Death Eater forces in the late hours of 1 May, 1998, prior to the Battle of Hogwarts that started at midnight the next day. The Death Eaters, on Voldemort's command, started bombarding the magical protection with spells, and it was ultimately brought down by a spell cast by Voldemort. In all probability, it is a spell calling for great power and expertise for its correct execution.[1]

Known casters


  • The incantation is likely derived from the Latin fiat, meaning "so be it," or fio, which is "to be made or done", or "to come into being", and durare, which means "to become hard or solidify."

Behind the scenes


Notes and references

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