Elec Man also has some great lines, helped by his excellently hammy delivery.
Proto Man and Oil Man.
Oil Man: Lookin' fine, bro! Check it out, we both got scarves! Now that's stylin'! Proto Man: Oil Man?! This being our first meeting, brother, I'll make this short, so hang on. Oil Man: Hey I give you a compliment and you ignore me! What's up, man? Ain't you gonna say somethin' about my scarf?
Cut Man (unsuccessfully) trying to communicate with the Yellow Devil. And it gets even better. The Yellow Devil seems offended by the attempt for whatever reason.
Some of the dialogue lines between Mega Man? and the Robot Masters are gold, due to the fake Mega Man always trying to convince the current RM to join them using their slang and a smooth, totally-not-a-bad-guy delivery, not unlike the Ruby-Spears Proto Man. However, Oil Man probably takes the cake.
Mega Man?: Oil Man! Bro! Dr. Wily's got some slick jobs with your name on 'em, so how about it? Oil Man: Ha-ha, real funny! If you're Mega Man, then I'm Dr. Light. Mega Man?: Guess our oily plan just burned up in my face... Better take this guy down!
This:
Copy Roll: How do you do, Original Roll? I bet you're worrying about your precious Mega... Ha ha ha...! Roll: What?! I-I... Th-that's not what I'm thinking at all!! Copy Roll: You and I are one in the same. I know everything about you. It's okay, I'll tell him for you. Or are you going to try to stop me?
Some of the Robot Masters are determined to bring their Copy back with them. Guts Man is impressed with his copy and wants to bring it back to work on construction with him, and Ice Man wants to freeze the "well-constructed toy" and bring it home. Both of the copies are horrified and confused about this. Cut Man also has an amusingly-positive reaction to his own duplicate: