Area 1 (US: Round 26)[edit]
This area contains ten Type 14 Special Invaders, twenty Type 15 Special Invaders, ten Type 16 Special Invaders, ten Type 17 Special Invaders and ten Type 18 Special Invaders in two separate horizontally-moving formations; the song you'll be hearing from the Yamaha YM-2610 is identical to that for World 1A, and there are sixty invaders in this area.
Area 2 (US: Round 27)[edit]
This area contains eleven Large Invaders, eleven Medium Invaders, and six Small Invaders, in a horizontally-moving formation; when one of them is hit for the first time, it shall split into two (which adds up to a total of fifty-six invaders).
Area 3 (US: Round 28)[edit]
This area contains fourteen Type 5 Circling Invaders and eighteen Type 6 Circling Invaders (in, as their name implies, a circling formation); the formation was first employed by the Flector in the first stage of Return of the Invaders (1985). Once you have cleared it, you will proceed to the second "Cattle Mutilation", but if you are playing the US version, you will proceed to World 3D or "Round 29" - the theme for which is, yet again, identical to that of World 1A (and this one).