DatTank.io is a free-browser game where you can build your tank and fight other players in a field.
When you first join the arena, you are put on one of four colored teams. Your goal is to destroy as many enemy tanks as you can and get the most points to become the leader! There are life and ammo packs all over the map, so if you get hurt in a fight, you can heal up and get ready for the next one.
Also, don't let the gun get too hot, or you'll have to wait a while before you can shoot again, which can cost you a life!
Have fun and good luck!