When comparing Freeciv [Free] vs Slither.io, the Slant community recommends Slither.io for most people. In the question“What are the best browser-based multiplayer games?” Slither.io is ranked 1st while Freeciv [Free] is ranked 4th. The most important reason people chose Slither.io is:
Anyone can play but if you want to get far you have to spend a lot of time on it.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Excellent depth
In Freeciv you have to take into consideration terrain, resources, cities, economy, units, combat, diplomacy, governments, technology, wonders and many other things both for your and all competing civilizations.
Pro Free, open-source & does not require a plugin
If your browser supports HTML5, just go to play.freeciv.org to start playing.
Pro Intelligent AI
Even on lowest difficulty, Artificial Intelligence of Freeciv will give you a run for your money.
Pro Observe public games
You can observe public games currently being played and even take control of an AI civilization to jump into the fight.
Pro Simple to get into hard to master
Anyone can play but if you want to get far you have to spend a lot of time on it.
Pro Short game
You can play for 5 min and then just quit.
Cons
Con Not a lot to do other than eat, eat, eat
There is not a lot to do so this will not be for everyone.