So, this recently happened to me in playtesting:
It's my upkeep. My opponent casts Mistbind Clique.
I don't have a relevant counter, but I do have Path to Exile. He has multiple fairies on the field, as well as enough mana to animate his Mutavault, so I can't get a two-for-one by Pathing anything before the Clique resolves. I let the Clique resolve.
Mistbind Clique's champion trigger goes on the stack. In response, I Path the Clique before its champion trigger resolves.
Path resolves.
What happens when the Clique's champion ability resolves after it's already been exiled?
My understanding is that my opponent still gets the option to exile a faerie (which would stay exiled, since the Clique has already left the battlefield). If he does so, though, does the Clique's tap-down ability apply?
When a Faerie is championed with Mistbind Clique, tap all lands target player controls.