To get this achievement you must have a band multiplier of 8. You must have all four instrumment players in your game. This can be done online or local. Each player can be on any and different difficulties. The star power guage must be half full to full to use it in solo, but in a band each lightbulb thingy with star power in it is a full use of star power. There are 6 bulbs meaning each player can use star power and stiil have 2 available uses left. To get the achievement you must each have an 8 times multiplier at the same time for even just half a second. This is easier on lower difficulty settings therefor it's harder to mess up. To get an 8 times multiplier you must either already have a 4 times multiplier by getting a 30 note streak then using star power, or by using it befor you have a 30 note streak and working your way up to it while you still have star power active. If you do this, make sure you can hit a 30 note streak befor the rest of the players run out of their star power.
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