Akkanvader/World 1

JP: きゃあでらっくす号 (Kyāderakkusugō) インベーダーの新型宇宙空母だ! (Inbēdā no shingata uchū kūboda!)

US: SPACE CARRIER IT'S A NEW INVADER-TYPE SPACE AIRCRAFT CARRIER!

Stage 1
Welcome to the game. This formation is initially comprised of: 24 "original-style" Large Invaders and 16 "original-style" Medium Invaders, as the original SI main theme starts to be heard from the ES-5505; however, once the background has faded in, they shall transform into eight Type 1 Invaders, eight Type 2 Invaders, eight Type 3 Invaders, and eight Type 4 Invaders as they start saying "Wa, wa, wa, wa" from it instead. Once you have cleared it, your two chosen ships will fly on forward to the second stage - which features even weirder-looking invaders.

Stage 2
This formation is comprised of sixteen Type 5 Invaders, eight Type 6 Invaders, eight Type 7 Invaders and eight Type 8 Invaders; they will also occasionally pause before continuing their descent. Once you have cleared it, your two chosen ships will fly forward to the third stage - which features eight very fat-looking invaders which will split into two when hit.

Stage 3
This formation is comprised of: eight Type 9 Invaders; when one is hit, it will split into two smaller versions of itself, and when one of them is hit, it will split into two more smaller versions of itself, adding to a total of sixty-four invaders. Once you have cleared it, your two chosen ships will once again start flying forward as the text of "BONUS STAGE" appears.

Stage 4 (Bonus Stage)
Two Type 1 Bonus Invaders shall escort two groups of ten Type 2 Bonus Invaders down into view, from the top of the screen; once you have fired a shot at each of them to kill them, two more Type 1 Bonus Invaders will escort two more groups of ten Type 2 Bonus Invaders into view, from the left and right sides of the screen. Once you have fired a shot at all of them, to kill them, two more Type 1 Bonus Invaders will fly into view from the left and right sides of the screen as twenty-four more Type 2 Bonus Invaders fly around them in clockwise and anticlockwise directions - and once you have fired a shot at each of them, to kill them, two more Type 1 Bonus Invaders will escort two more groups of seven Type 2 Bonus Invaders into view, from the left and right sides of the screen. Once you fire a shot at all of these to kill them, two last Type 1 Bonus Invaders will escort two last groups of seven Type 2 Bonus Invaders into view, from the left and right sides of the screen; once you have fired a shot at each of them to kill them, you will receive 1000 points for every Type 1 Bonus Invader and 500 points for every Type 2 Bonus Invader you killed (your maximum is 22800).

Stage 5
Once your two chosen ships have stopped moving on forward, the first Boss Invader will drop down into view, from the top of the screen and speak the threescript text Kondo ha, 'bosu' no oresama ga aitedā!! (今度は、「ボス」のオレ様が相手だー!!) in the Japanese version, or "THIS TIME, I, THE BOSS FIGHT AGAINST YOU!" in the US version; he shall then start flying around above you, while spewing a volcanic hail of bullets and bombs down at you (the latter of which can get blocked for extra points). He shall then throw two bowling balls down at you and spew out twenty-four smaller versions of himself - which shall adopt a vertical formation, as they descend towards the bottom of the screen, so you shall have to kill them as well. Once you have fired out enough shots at him to defeat him, he will explode, and speak the Hiragana text Chikushō, oboe terō!! (ちくしょー、おぼえてろー!!) in the Japanese version; you'll then receive 10000 bonus points, as your chosen pilots speak the Kanji/Hiragana text of ''Rakushō! Chō rakushō! Pīsu!'' (楽勝! ちょー楽勝!! ぴいすっ!) in the Japanese version, or "WALKAWAY!! A VERY EASY VICTORY!" (in the US version). The screen will now fade back to the overworld map as they proceed up onto World 2: "Oishin Hoshi" (おいしん星) or "Gourmet Star".