9 Harry Potter Mysteries and Plot Holes The Filem Left Hanging

Flickerflame 2. The ingredients for Polyjuice Potion are difficult to get, unless you can raid Snape's stores. You need some DNA from the person you're impersonating. It also wears off after an hour, which makes it a bit impractical for long term use. 6. Maybe Voldemort realised that making such a demand would offend some of his followers (I think Bellatrix, for one, would be insulted by the suggestion that she'd need to be forced to be loyal). Others like the Malfoys would abandon the cause if they were asked to take such a risk. Maybe Voldemort was just too arrogant and assumed his Legilimency was skilled enough to spot any potential traitors. Or maybe the spell didn't exist during the First Wizarding War (the first chronological mention of it is during Ron's childhood, which would have been after the first war's end), though that wouldn't explain why it wasn't used after his return. 9. Maybe legal Portkeys have a time setting, as an additional security measure. Crouch Jnr wouldn't bother with that because he knew that he couldn't predict when Harry would reach it. It also didn't work on those who set it in the centre because Crouch hadn't turned the Cup into a Portkey yet.