Boss Weapons
In the tradition of the MegaMan X series, your playable character gains the powers of each main Maverick. X gains a special weapon, Zero gains a saber technique, Axl gains an A-Trans transformation, and Synthia gains a weapon mod.
Special Weapons
Special Weapons are what X gains from defeating the main 8 bosses of the game. They consume ammo, which can be refilled in a variety of ways.
Techniques
Zero gains an array of saber and melee techniques from bosses that are performed with different commands. In Corrupted, Zero's special moves draw from a special Saber Meter which refills over time. It starts with 2 energy, and can be expanded with upgrades.
Transformations
After beating a boss, Axl gains the ability to temporarily transform into that boss to perform an attack. This goes against canon, since Axl could only copy Reploids approximately his own size. ...Unless we're in the Command Mission timeline?
Mods
When Synthia defeats a Maverick, she collects a blaster mod which can be combined with other mods, with stacking effects. At least, that was the old system. It may or may not end up being reworked; this section is being ignored for now.