The only things about a game that can be trademarked or copyright are:
Graphics
Music
Sound
Text
Level Layouts
Names
Titles
Trademarked Characters (mario, sonic)
Code
How the game plays, and even the general layout of the interface can't be protected. SO you can make pacman with all that diff. and it is not just legal, it is considered a completely different game.
Graphics
Music
Sound
Text
Level Layouts
Names
Titles
Trademarked Characters (mario, sonic)
Code
How the game plays, and even the general layout of the interface can't be protected. SO you can make pacman with all that diff. and it is not just legal, it is considered a completely different game.