Mega Man Ripping Project (Classic/X)

[Magma MK-II]

Mega Man 3: Kamegoro Maker, Yellow Devil MK-II, Wily Machine, Gamma
Mega Man 5: Big Pets, Circling Q9, Wily Machine, Wily Capsule
Mega Man 6: Rounder II, Power Piston, Mettonger Z, X Crusher, Mechazaurus, Tank CSII, Wily Machine, Wily Capsule
Wily & Light's Rockboard: all character's sprites
Rockman & Forte: Mirai Kara no Chousensha: all enemies and bosses
Mega Man: The Power Battle: Wood Man, Heat Man, Gyro Man, Napalm Man, Cloud Man, Junk Man, Slash Man, Shade Man, Turbo Man, Yellow Devil, Van Pookin, Wily Machine
Mega Man 2: The Power Fighters: All Robot Masters and fortress bosses

As far as I see, both Wily Wars and the two Xtreme games are only missing stages.