Is there any way to cleanse, remove, or stop a fiora ulti?

E

Zhonya's

Best way to neuter her ult... be out of range of it. Played against a Jungle Fiora last night, he blew his ult a couple times and we all flashed out of it. Another time, Malphite just ult'd into her and we then burned her down before she could hit it.

Stealth and Zhonya's will both prevent the damage. She is also vulnerable to AOE and turrets (including Heimer's) during the moments she appears and deals damage.

your death

If you're AP - Zhonyas

If you're AD - Nope! Just die :P Or play Vayne and use your invistumble. I think that breaks it.