Just Cause 3 is expected to release this year, and it's looking ridiculous to boot, but there's still plenty of time to catch up with its amazing sequel. Just Cause 2 is still one of the most anarchic, ridiculous and plain fun sandbox games ever made, and better yet, you can get it for under £2.
Use voucher code H3U5TZ-9726D1-JIPSHC. Remember that there are loads of mods available too. Thanks to Jesse148 @ HUKD!