Warin.space is a about a war that takes place in outer space. You must join a fleet to help innahilate your opponents. You have the ability to customize your ship, declare war, etc. Warin.space game places an huge emphasis on specialized ships and teamwork.
Blash.io is a 2D single player war game in which you shoot certain substances to your opponents and gather food to get bigger. unblocked at school game.
DogFightx.com is a 2D multiplayer game in which you have control over an aircraft. You will fly through the playing field and dodge bullets, bombs, etc. maneuverability is key in this game.
agma io is a widely popular 2D online action game. In this game, players command a cell which looks like a ball. Agma.io Free Multiplayer Game | Dominate the World
BigHero.io is the hack n slash style game in which you control a character from a top-down view and must kill everything in sight. In this world its win or lose there is no other option so make sure you time your attacks accordingly to hit your enemies with your weapon before they hit you.