I play it too!I enjoy Kingdom of Loathing! It has the energy system found in many mobile game but the humor is really nice.
Costume Quest? Now that's a name I havent heard for years!! Thank you for making me nostalgic. It was my sisters favourite game. We have finished Costume Quest 2 over 30 times. I love the plot, the style, the jokes. I haven't played it since I was 7 or something. Now forgive me, I have a game to download (costume Quest)!!!A lot of the free games on epic are pretty good. They cycle through different games to be free each week but my favorites of them are 3 out of 10 (Episodes 1-5 I think are just always free) Costume Quest (There's a sequel too but I'm not done with the OG yet) Alto's Adventure, FEZ, and Pikuniku. Some good ones on steam are Bone Voyage (I can't progress because of a bug) and The Adventures of Nick and Willikins (look at EVERYTHING).
Oh yes Fireboy and Watergirl's game it's a very beautiful game, I remember that I used to play it with my friends or my sister and we always shouted to each other !Fireboy and Watergirl 1!