Mandalorian Neo Crusaders
this was the name given to the first groups of beings who were recruited by the ancient Mandalorian Crusaders to join their ranks and fight alongside them in the Great Last Battle. These Neo-Crusaders became what many modern military experts consider the Mandalorian shock troopers, a collection of beings from disparate races and backgrounds who banded together under the tenets of the ancient Mandalorians. The armor worn by the Neo-Crusaders was much bulkier than that of their predecessors, but was designed to withstand blaster fire and to identify the wearer as a Neo-Crusader. This armor was not studded with weaponry, but was efficient and functional. Individual Neo-Crusaders painted their armor as they wished, allowing for a variety of color schemes. It was the Neo-Crusader armor that later became the design basis for the Old Republic's Senate Guards
This was the name used by the survivors of the Mandalorian Wars and the Old Sith Wars to describe their loose brotherhood. After the combined forces of the Old Republic and the Jedi Knights virtually wiped out the Neo-Crusaders, the surviving Mandalorians were forced to go into business as mercenaries to stay alive. Disparate clans of mercenaries were formed under the guidance of the old Mandalorian Canons of Honor, but these new Mercs worshipped the credits in their bank accounts more than anything else.
Mandalorian Death Watch
this elite group of Mandalorian Mercs split off from the true Mandalorian shock troopers when Vizsla rebelled against the leadership of Jaster Mereel. It was believed that the Death Watch was destroyed at about the same time as the rest of the Mandalorians, during the Mandalorian Civil War, and their order became something of a legend. During the height of the Galactic Civil War, Boba Fett discovered that the Death Watch sect was still operative, having contracted with Black Sun for addition manpower and secrecy. During this time, their base of operations was hidden in the Red Sin Chimaera Nebula, near the Forest Moon of Endor. The armor of the Death Watchmen was distinctly different from that of the True Mandalorians, although the differences were in color. All Death Watchmen wore stark black armor, and their helmets were modified slightly to further distance themselves from their counterparts. The Death Watchmen were also only group of Mandalorians to regularly wear Mandalorian Crushgaunts, which had been outlawed by the Mandalorian government centuries earlier.
Mandalorian Death Squad
this was one of the most violent branches of the Mandalorian military, during the years leading up to the Battle of Naboo
True Mandalorians - Mandalorian Warriors reunited by Jaster Mereel approximately two decades before the Clone Wars. They followed the supercommando codex which taught them an ethic that extended beyond the limited idealogy of fighting for credits. Existed until around 36 or 35 BBY or so, until revived on two seperate occassions by both Alpha-02 and Shysa and referred to as "Protectors".