The Mega Drive was one of the most successful consoles ever, with over 700 games released and plenty of classics. Not all the games can be winners however, and the Mega Drive like all consoles has its share of duds. Here are just a few.

World Cup Italia '90
Sega

Oh my. World Cup Italia '90 is top down soccer gone horribly, horribly wrong. Granted top-down soccer games aren't all that great (especially compared to FIFA), but this one is exceptionally bad. If birds-eye view soccer is your thing then check out Super Kick Off and leave this trash alone. An obscenely common cart (also sold as part of a 3 pack in Aus), you'll probably acquire this in your collection without trying or even wanting it. Sort of like the flu.

Spider-man and X-men: Arcades Revenge
Flying Edge

Spider-man is cool. X-men are cool. What could possibly go wrong?
Quite a lot actually: The character sprites in Arcade's revenge are ugly and poorly animated, the levels are dull, the controls are sluggish and to top it all off- cyclops looks terrible in blue. The web slinging gameplay of the first level where you play as Spiderman is actually pretty decent, but the level itself does not do justice to the mechanics. It's all downhill from there.
Get one of the other Spider-man games- they're all better. Same goes for the X-men.

Action 52
Active Enterprises

Carrying on the tradition as one of the worst NES titles, Action 52 for the Mega Drive is a simply woeful collection of 52 awful, awful games on 1 cart. The only way to play this collection of messes is with a friend; taking turns trying to pick the worst game on the cart. We decided it was the mine-sweeper clone, but the ski-free clone and slidey puzzle game both come close. Unless you're going for a complete Genesis collection, steer clear of this one. You have been warned.

F22 interceptor
Electronic Arts

One of the problems with retro gaming is no matter how hard you try, some games are just very difficult to play today. There is a smoothness to modern 3D that makes it really hard to play a 16-bit flight sim in what feels like 5fps. In some cases you may even feel nauseous.
F22 Interceptor by EA was the first flight sim on the Mega Drive and scored relatively good reviews when released. In light of better sims such as F117 Nighthawk and Mig-29, F22 Interceptor quickly began to pale and even by 95 it was regarded as a dog of a game. Like World Cup Italia 90' it is a very common cart to come across, but the longer you can avoid buying it the better.