by boardmathias
I have played about 50 games of Terra Mystica and 2 Games of Gaia Project.Terra Mystica is the more elegant design.
Gaia Project feels like an evolution of the original prototype. Like the thing the designer brought to the publisher and then the publisher said: This is great but we need to streamline it.
Terra Mystica is this streamlined Gaia Project.
So if you played hundreds of games of Terra Mystica and you want more: Play Gaia Project.
Otherwise stick to the more streamlined Version. Terra Mystica has less rules and provides a very similar gameplay experience.
Once you think you have seen everything Terra Mystica can give you and you still want more of the same: Go for Gaia Project.