Be careful what you wish for...

[The Elf-warrior]

I wish Balrogs had wings.

Your wish is granted. The Balrog flew out of the chasm and toasted the Fellowship to death, took the Ring, and became the Dark Lord of Moria. Sauron sent in the Nazgul on flying steeds. They recovered the Ring and gave it to Sauron, who plunged the world into a second darkness.

I wish Denethor wasn't such a pyromaniac.