That's it, free games. I'm not giving a strong recommendation, but I played the first new one and thought it was worth it. Considering that it came free with my graphics card at the time.
Also if you have an AMD card, be sure to turn on TressFX for better hair quality.
Definitely worth it for free, the first game doesnt really have that many puzzles, but they fix that in the two other ones. The series has a lot of similarities with Uncharted, which might be a good thing or a bad thing depending on how you like it. Always enjoyed going full melee and :pika-pickaxe: people to death.