Tank Riders is a nice arcade game with 3D graphics. In this game, you control a tank and you should come through a lot of different levels, in which you should shoot down enemies and avoid obstacles. Your goal is to complete the levels as fast as you can without getting killed and, ideally, without being hit by enemies. This is a lot harder than it sounds, because there are multiple enemies in each level and the obstacles become harder and harder.
There are two game modes: single-player and multi-player. When you start playing the single-player mode, there will be three different campaigns that you can complete. The first one is called "Intro" and it serves as a tutorial on how the game is played. This one has 15 different levels. Then the following campaigns, campaign 1 and campaign 2, have 30 and 45 levels respectively. As you progress through the game, new weapon systems will become available to you.
Briefly, Tank Riders is a nice game. It should keep you entertained for a while. Some levels are challenging but most of them can be completed on the first try.