A large scale organization based around the idea of protection and defense for the people of earth and most of the planets controlled by the Galactic Federation. When the Galactic Federation planted a bounty on samus's head they set in motion a plan that would overthrow the federation and install a new government governed by their supreme leader: General Osiho. They are in full support of the idea to derail the Federation but their plans are much darker and if they were to rule, Then mankind would crumble.
The Alpha Legions are comprised of elite troops called Black Masks because they cover their faces with black headgear with a small visor at the front. They carry with them large plasma axes and rarely hold powerful plasma hammers (Which are for commanders or squad leaders), At the back of their suits are large oxygen tanks as the suits provide no open areas to take in oxygen that if they were struck upon would send them flying out of control and since they are connected to plasma tanks, Would explode and cause a blast area around him killing others as well, thats why they tend to fight alone due to their size and strength. The legions also send out fighter drones to fight as well if the battle is life threatening to their oxygen tanks.
Their commander is rarely seen but is heard on speakers or on large tvs around the earth broadcasting propoganda 24/7. Some say Osiho came from the earth colony on K-2L and was sent to earth before the space pirate invasion. But that is just a rumour.