As I played the ColecoVision port of Mr. Do!, I suddenly executed the "all EXTRA letters in red" glitch.
How did this happen?
I attempted to power ball the "E" Alphamonster, but a Chomper dug the path enough to knock an apple down my way. The apple crushed the Alphamonster, Mr. Do! and a Badguy all at the same time! But instead of going to the usual green extra life award screen, I instead lost my present life. When the game then restarted, all the letters of the word EXTRA are red! This glitch means no more Alphamonsters and thus no further opportunities for extra lives unless you either reset your game or keep playing until you lose your last life and play another game (pressing either * to replay the last skill level you choose or # to select a different skill level)!
Here's an attachment of my experience.
Thus I ask you all ColecoVision Mr. Do! players: have you ever done this glitch at least once?
~Ben