Deep in space, a convoy of aliens has blocked your path and challenged you to war! This may not seem like a particularly fair war, pitting dozens of them against only one of you, but with fast reflexes and a trigger-happy offense, you just might have an advantage.
Four types of aliens make up the convoy. Drones are the most plentiful and the easiest to kill. Emissaries fly more unpredictably and are harder to pick off, often moving in sharp zig-zags toward your ship. Escorts protect the Galaxian flagships, often flying together with a flagship in a single attack. The flagships themselves are the most lucrative targets, and consequently the most distracting. All aliens first appear in the convoy, but then frequently break formation to attack you individually, or in groups of one or two escorts plus a flagship. Aliens are worth more when attacking, so you may not want to pick too many off before they move. Escorted flagships are especially valuable when attacking, but be careful not to get caught in their deadly rain of fire!
After an attack, any aliens still alive will rejoin the convoy, until there are only a handful of survivors. Then, it's kill or be killed, as the aliens move continuously, either until you're dead or there are no aliens left. Wiping out the last alien may feel victorious, but then a new convoy will appear, offering an even greater challenge than before. Good luck!