Sky Nations is a multiplayer sandbox game where players can join together to build air ships(cannons and all!) and do battle across a vast world procedural world full of relics and machines from another age waiting to be plundered by daring sky captains and their motley crew.
As of recent updates my rating has turned into an 8.5- if I were capable of doing so. The up in rating is because of resolved balance issues, a larger community, and just plain smoother gameplay. Again, my rating will go up again in the future and will most likely, at some point, reach a solid 10.
Pros:
Nice community and supportive admins
Ships can be built and piloted smoothly with few restrictions
Large amount of craftable items
VERY original concept- very few other games I've seen are remotely similar to this, all in all.
Thousands of possibilities when building, extremely customizable!
Vast map with multiple types of islands (and promise of more being added soon)
Ability to create your own servers
Cons:
Ship thieft- you'll be lucky to find your stuff in one piece the next day
Difficulty to find certain materials. Or so people say... I myself am fine with how it is.
Few usable weapons
Some blocks are admin-spawned only
In conclusion, this game is definitely on the rise, with the only limit being how fast it's being developed.