Updated: Feb 22, 2021
Daikaiju Monogatari: The Miracle of the Zone II did not start at all, so I skipped it. It was a port of a SNES RPG that looks cool from screenshots, so it's a little disappointing that it doesn't work.
CyberTiger (Electronic Arts/Xantera, 2000)
I fully expected another mascot platformer, and instead I got a golf game starring Tiger Woods as a child. You select clubs with up and down and then control your aim with left and right. But instead of actually moving left or right, pressing those buttons moves you around the circumference of a circle that. You might reasonably point out that all points on a circle are not remotely equidistant to some other point outside the circle, but the game does not care. That's how you get to aim.
Cyborg Kuro-Chan: Devil Fukkatsu (Konami, 2000)
An autorunner where you shoot background scenery to get powerups and sometimes have to jump over clutter or shoot an enemy. It might've been fun as a minigame to add variety to a platformer, but it's not interesting enough to sustain a whole game.
Cyborg Kuro-Chan 2: White Woods no Gyakushu (Konami, 2000)
So naturally they made a sequel that's the exact same thing. The only difference I could see was that my bullets didn't seem to actually collide with anything this time.
Daa! Daa! Daa! Totsuzen ★ Card de Battle de Uranai!? (Video System, 2000)
Holy moley this game sucks. It's a race to get rid of 5 cards. You pick one to play, and then your opponent needs to play another card that's higher or pass. They also have one chance per round to use a special ability, which in my case boosted a card by +2, and one chance per turn to exchange a card with the deck. If you win, you play first next round. This is almost entirely a game of luck, and you could play it with a regular deck of cards. Why does this game exist?
Daffy Duck: Fowl Play (Sunsoft, 1999)
Daffy is fighting a bunch of dogs and chickens for some reason, which means throwing dynamite at them and not stepping on all the mouse traps and rakes that have been strewn around the farm. He's also quickly starving (the 70% in the top right), so you have to eat food all the time or he'll die. It's bad.
Daiku no Gen-san: Kachikachi no Tonkachi ga Kachi (Gaps/Biox, 1999)
A game where the sound of the title is much more important than the meaning. Robots have taken over your town, so you need to go beat them up with your magic hammer that turns them into blocks. Then you can push them on to buttons and do other puzzle platformer things to get through the level. The hammer was surprisingly versatile even in the opening levels, and I've just noticed in the screenshot that it looks like you have three different ones to use. I enjoyed it.
Dance Dance Revolution GB: Disney Mix (Konami/KCET, 2000)
DDR with Disney characters and songs. They insisted on having you press two directions at once, so they couldn't just use the d-pad for controls. Somehow that led to the decision to map d-pad right to left, d-pad down to down, A to right, and B to up. This is unplayable.
Dance Dance Revolution GB, GB2, and GB3 (Konami/KCET, 2000, 2000, 2001)
The same game three times. Unlike the Disney one, they do not use double presses and the directions are all just mapped to themselves. It's much more playable and the music is better, but I still think you'd have to be pretty desperate for DDR to want to play on GBC.
Dancing Furby (Tomy/TOSE, 1999)
A rhythm game where your Furby makes weird noises and sort of shudders to the beat of nursery rhymes. The rhythm minigame itself is fine, but, like, why? Why was this made?