Sheikh Hassan bin Hebat Allah was the religious leader of Yam. He responded to Ajman's request and called for the general mobilization to Adderyah in Riyadh with 500 men on 500 black horses (one of their techniques in war).
Sheikh Hassan bin Hebat Allah, the spiritual head of Yam, responded to Ajman's appeal and orchestrated a massive call-up of troops to Adderyah in Riyadh, dispatching 500 men on 500 black horses (a military tactic characteristic of his forces).