Abdaals

Nabi (Sallallaahu Alayhi Wasallam) is reported to have said, 'Abdaals will be found in Shaam. They will be forty in number. Whenever one of them passes away, he will be replaced by another. It is through them that Allah Ta'ala will cause it to rain and also grant the Muslims victory over their enemy and remove a possible punishment.' (Musnad Ahmad)