The so called „Army of Mujahedeen“ is the group being most active in fighting against ISIS in Syria. Some mainstream western and arab media tried to imply that this group – as it is fighting „Al Qaeda“ (ISIS) – is (and must be) „moderate“.

Here one can read which specific rebel battalions belong to the „Army of Mujahedeen“:

„The Army of the Mujahideen was formed out of the following factions: the 19th Division of the FSA, the group known as Fastaqim Kama Umirt, meaning “Be Upright As Ordered,” the Nur al-Din al-Zanki Islamic Brigades, and al-Noor Islamic Movement…Meanwhile, the influence of the Nur al-Din al-Zanki Brigades covers areas in the northwestern countryside of Aleppo, such as Anjara, Hour, Mansoura, and Kafr Dael. These brigades are believed to be the strongest among the constituents of Army of the Mujahideen.“
http://english.al-akhbar.com/content/syria-army-mujahideen-challenges-isis-gains

It is quite interesting to know who „Nur al-Din al-Zanki“ was in order to get a clue about the ideology and mindset of the fighters of such a rebel militia:

„In 1146, Nur ad-Din massacred the entire Christian population of the city [Edessa]“
http://en.wikipedia.org/wiki/Nur_ad-Din,_atabeg_of_Aleppo