Reading a formation in Harbour Watch
Every wave has the same three phases. Knowing which one you are in tells you where to be.
Phase one: the entry
Groups fly in one after another along curved paths: wide arcs from a side, loops from the top, low sweeps that skim the bottom of the screen before climbing. While they fly in they are strung out in a line, and that line passes through the same point for every member of the group.
Stand under the end of the curve and fire. You meet each member as it arrives, often clearing half a group before it reaches its place. Low sweeps are the exception — they pass close to you, so let those go by and shoot them from behind.
Phase two: the formation
Settled enemies sway left and right together near the top. The orbs shoot at where you are, the hexagons fire spreads and the darts wait for their moment to dive. This is the time to remove the hexagons: three hits each, and the fewer spreads in the air, the more room you have.
Work from one side of the formation to the other rather than picking targets all over it. Your shots are in the air for a while; a steady sweep lands more of them.
Phase three: divers and raiders
Darts break off and swoop at your craft, and from wave two raiders cross on a weaving path. A diving dart is worth double, and it flies straight down for its last stretch: if you have a shield charge, hold your position and shoot up its path.
Raiders never join the formation. Shoot them from the side they enter; chasing them across the screen pulls you into aimed fire.
Moving well
Never stop completely. Aimed shots go to your current position, so a slow drift makes most of them pass behind you. Keep to the lower part of the screen and leave yourself room on both sides.