Light is key : too specific, a lot of people will end up doing the same thing i guess...

Evolve : why not, could be cool to be honest

You start with everything and end with nothing : clearly too specific, once again a lot of people wil end up doing the same thing...

Four elements : once again too specific

Decay : I don't like this theme too much but i can be a cool one so why not

Use the enemies to win : meh.

Duplication : why not... But I feel it a little too specific !

Expanding environment : same reasons than duplication, why not but it seems too specific to me

Safe in the dark : It's a bit better than Light is key to me, i'm not too excited by this one but why not.

Tiny machines : to be honest i really like this one !

3 Rules : too specific i guess, and seems a bit boring an restricting concerning the genre of the game

You can't control the player : a lot of themes look like this one and I really don't get the concept

Alchemy & Magic : even if the theme is not about a gameplay feature or restriction as usual i kinda like it

Four-colour palette : it's only restricting the graphism, not the gameplay, and since a lot of contestant won't really focus on the graphisms...

What you create you must destroy : I just really don't like this one

One of you is a traitor! : it seems a bit too specific for me but why not