I just glanced at the title and thought it said "Worst conversations".

LOL! I was thinking the same thing. It must be getting late somewhere in the world.

Pit-Fighter got some terrible conversions to home consoles and computers.

Here is the arcade game:

http://www.youtube.com/watch?v=LeNwY_5gj1k

Now please explain to me how these conversions are the same game? 

http://www.youtube.com/watch?v=T1I82SmRgEo

http://www.youtube.com/watch?v=gmLy-S5KKCg

http://www.youtube.com/watch?v=Kj2AD2t31yk

If you squint really hard it looks like Pitfall. I mean Pit-Fighter.

Another worthy contender, Road Riot on the SNES:

http://www.youtube.com/watch?v=C5KbgyQIELg

Here is the original arcade version so you can compare it properly:

http://www.youtube.com/watch?v=IpY_MLlbtWY

I wonder what is their excuse for this.  It's not as if the SNES couldn't do a proper port of the arcade.

I wonder what is their excuse for this.  It's not as if the SNES couldn't do a proper port of the arcade.

Shit programmers, THQ did it IIRC and their 16-bit games were well known for being utterly terrible.

Just look at how good the Lynx version is of this game.

The first attempt at Defender on the 2600 was a big disappointment for me. The above average flickering was annoying but almost forgivable - it was the fact that when you fired your spaceship disappeared....the game code must use the same hardware sprite for the ship and the gunfire - heartbreaking.....

However I played it a fair old bit - clocked the score (999,999) and clocked the wave counter too (99) so it couldn't have been that bad!!  Play wise it was quite good but I couldn't play it now.

Defender 2 blows it away and Chopper Command by Activision is a decent alternative

Some great comparisons. Keep them coming 

Here is the most extreme one I have ever seen! Space Harrier got some bad conversions but this one for the Sharp MZ-700 takes the biscuit!

http://www.youtube.com/watch?v=cs-4Zu0DN2g

To be fair, given the MZ-700's weak capabilities this was probably more an exercise in trying to create something that was even vaguely recognisable as Space Harrier than something anyone would genuinely play for fun.

Here is the most extreme one I have ever seen! Space Harrier got some bad conversions but this one for the Sharp MZ-700 takes the biscuit!

http://www.youtube.com/watch?v=cs-4Zu0DN2g

This is honestly interesting, if only as an experiment to see how much you can break down a game and still have it look vaguely like the original title.

I'm an Atari ST fan and always have been so I've been on the receiving end of more than my fair share of bad conversions.

The ones that spring to mind right now are Street Fighter 2 (I'd played it on the arcade and SNES by this point, was so excited that it was coming to the ST, I even upgraded to 1MB of RAM to play it. It wasn't too bad if you like muddy visuals that move at about 2fps and a stunted move set completely inaccessible due to unresponsive controls) and ESWAT (I thought this game was awesome on my friend's Megadrive, but I don't think the ST was built for this kind of thing 😀

Although it's by no means a terrible game, I've always hated the Speccy version of Nemesis. They managed to suck all the playability out of the game.

Actually Konami did a pretty lousy job of converting all their games to the Spectrum - Jackal and Jailbreak were pretty pants too. Should have left it to Imagine.

Have to post this horrendous mess too:

Kung Fu Master on the Spectrum:

http://www.youtube.com/watch?v=A7qQO43SDN0

Arcade version:

http://www.youtube.com/watch?v=EgO4HtWIJjQ