Every Extend Extra Extreme is one of the games I’ve been totally been going crazy for recently. I tried the demo on Xbox Live Arcade and was instantly hooked. Explaining how it works is quite tricky… Wikipedia to the rescue
the player controls a ship which they can detonate at any time. This causes any enemies within a certain radius to explode, which in turn cause other enemies to explode in a chain reaction. As the game continues more and more enemies populate the screen allowing longer and higher scoring explosions. The player may halt the chain at any time to pick up power-ups (such as to increase enemy speed, add time, add temporary shield) or to start a new chain reaction.
The explosions add a percussive beat to the background music.
The player’s ship is destroyed when coming into contact with or being shot by an enemy while the player’s shields are down. This resets the level to its initial slow pace and bonus multiplier, therefore hindering the player’s scoring.
The one thing it doesn’t say is depending how your timing is with the beat, you get a small to large explosion radius. So bang on and you get something which can start a massive chain reaction while off beat and you only take out a few enemies.