it's a variation on missile command, Stratos arcade quality sound and enemy behavior all likeable, once you figure out how to shoot. a first glance has its controls looking like garbage, but you really have 2 cannons in the corners that fire together then ricochet off the crosshair to the left and right. don't try placing the crosshair on enemies, aim to the left and/or right of your crosshair. eventually one cannon can get knocked out and you work with half your firepower. at full strength you can aim left and right together then knock out 2 enemy with one shot, knock out all 3 with 1 shot when very lucky. lookout for meteor impacts after clearing wave one.