Cyber elves are programs that help you on your missions. There are three types of Cyber elf. One is the Nurse, which heal and increase your vitality in some way. Next is the Animal type, they help you with movement. The last is the Hacker type, they hack the area around you to give you bonuses like more items and abilities in battle or freeze enemies. In Megaman Zero 3, there are Fusion elves and Satillite elves. Fusion elves are elves you can use only once, then they die and dissapear forever, like in the first game. Satillites over around you but dont die, using their respective abilities at all times. You can have up to two Satillites around you at one time. It' sup to you to decide whether to use them as Satillites or get their abilities permanantly by Fusion type. E-Crystals are what you feed to Cyber elves to level them up and change them to either Fusion or Satillite. This is al lthe cyber elf knowledge I know