Re: Signs of Mahdi
the Prophet SAW said words to the effect : “all prophets warned their people about the false messiah (dajjal)” alongside the false messiah comes the true Messiah (Isa ibn Maryam AS) so from this in my opinion the messiah-ship is a belief of which we will find remnants of in other religions. false claimants to messiahship are many, all the ideologies i know which do this end up with false messiah even though they are trying to replicate true messiah
the mahdi in islam will just be a leader of the revival (fightback of muslims). we (ordinary muslims) are required to fightback alongside him as this is last chance to follow what Allah SWT commanded of us.
there are references to end of times in the Quran and hadith, they show the disbelievers/gog/magog/dajjal devouring the muslims. the scenario is not something deniable for muslims
with the permission of Allah, i have been helpful to you in making sense of the different claims