Invocation for Allah's protection from the False Messiah

 199. Whoever memorizes ten 'Ayat (Verses) from the beginning of Surat Al-Kahf, will be protected from the False Messiah 1 if he recites them in every prayer after the final Tashahhud before ending the prayer, seeking the protection of Allah from the trials of the False Messiah.

Reference:
1 Muslim 1/555, another version mentions the last ten 'Ayat, Muslim 1/556. 
2See invocations no. 55 and 56 of this book.