Well, last night, I got set for a few hours of CV Lord of the Dungeon. Plugged it in, made sure everything was just right, so no RAM corruption, the usual.
First, go to Diane's Drinking Depot, to collect the characters I spent weeks building up.
Glitch!
Turn off game. Try again. Oh, good- everything seems fine...COLOR CHAOS.
Well, that's that.
Take apart cartridge. Take out battery. Clip it on to the trusty old Radio Shack Battery Tester. Sure enough, it was pretty much dead.
That's one obvious advantage of using passwords or codes...