This was my first game, and to see the full box means a lot! I FINALLY DESTROYED THE 8 MAVERICK REPLOIDS!!!!
To anyone who needs help, here you are.
Chill Penguin<Flame Mammoth<Storm Eagle<Sting Chameleon<Boomer Kuwanger<Launch Octopus<Armored Armadillo<Spark Mandrill who is weak to the first Maverick on the list, who uses Shotgun Ice. I, however, killed Chill Penguin and Storm Eagle with the X Buster.
Yeah, I figured it out, too! It actually can go both ways; Sigma either got his scars from his first encounter with the crazed Zero, or from X's "shining finger" hand from the Day of Sigma short film found in the PSP remake of the first Mega Man X.