Dragonsphere is a great adventure game. The puzzles are clever and often based around what you know and hear about the different cultures in the game. There's a couple of really tough puzzles (there is only one which feels like it's been made more difficult for no reason) but mostly it's pretty logical and down to your adventuring/diplomatic skills. Though I enjoyed the setting I feel like many areas could be more fleshed out and by the end of the game I wanted much more - but, as with many things, this is a testament to the final work as it stands. Finally, though it's perhaps one of the game's most prominent features, the music is incredible - though at times a little haywire. Overall I'd say It's one of my favourite adventures I've played- I love it! And it's free...just make sure you get round to playing it!
