F1 Spirit, definately.
What about Salamander? You can power your ship up and up and acquire new powerful weapons (meteor laser and other of that ilk) while the co-player help by repeatedly crash his/her ship. I used to fully power up my ship before I go to next levels. The joy of the experience still lingers
Herzog and F1spirit
Oh, Herzog... How I didn't remember to say that. That's a great game!
Magical Labyrinth from Gigamix
Quarth is a lot of fun in 2 player mode as well, but my favourite is still Super Runner.
Herzog and Quarth, yes! Why didn't I think of those too? ... And how many hours did I enjoy Bombaman and Witch's Revenge with friends, while I was still at school
Since Herzog is already mentioned, I'll suggest BMX simulator!
Super Runner is very cool, I agree with kanima
I would like to revive a bit this thread. I'm preparing my OneChipMSX for easy transporting to friend's homes looking forward one of these weekend night playing videogames along with pizza and beer
I'm not used to play MSX games with other people, so I don't know what are the best multiplayer titles. Some of them have showed up here, but I think that there are more. Any ideas?