Once your (or both) Mega Blast have reappeared on the screen, a group of eight Type 1 enemies will come flying towards them from the right side of the screen while firing projectiles at them; once you have fired a shot at each of them to kill them the fourth and eighth ones will leave two blue device packs behind. Once you have collected them a group of six Type 5 enemies will come flying towards you from the right side of the screen while firing beams at you - and once you have fired a shot at each of these to kill them, the third and sixth ones will leave two more blue device packs behind. Once you have collected them your (or both) Mega Blast will start moving upwards as a group of eight Type 8 enemies comes flying towards them from the right side of the screen while firing projectiles at them; once you have fired enough shots at each of them to destroy their barriers and kill them, the fourth and eighth ones will leave two more blue device packs behind. Once you've collected these, a group of eight Type 9 enemies will come flying towards you from the right side of the screen, while firing projectiles at you - and once you've fired enough shots at each of these to kill them, the second and eighth ones will leave two more blue device packs behind (while the fourth and sixth ones will leave two red device packs behind). Once you've collected them, another group of eight more Type 8 enemies shall come flying towards you from the right side of the screen, while firing projectiles at you; once you fire enough shots at each of them to destroy their barriers (which will shrink down with each hit landed on them until they disappear) and kill them the tenth, twelfth, fourteenth and sixteenth Type 8 enemies shall leave four more blue device packs behind. Once you have collected them, your (or both) Mega Blast will start moving downward as a third group of eight more Type 8 enemies comes flying toward them from the right side of the screen while firing projectiles at them - and once you have fired enough shots at each of them, to destroy their barriers and kill them, the twentieth and twenty-fourth ones shall leave two more blue device packs behind. Once you have collected them, a group of eight Type 2 enemies will come flying towards you from the right side of the screen; once you've fired a shot at each of them to kill them the seventh and eighth ones shall leave two more blue device packs behind. Once you collect them your (or both) Mega Blast shall start moving downwards again as another group of eight more Type 2 enemies comes flying towards them from the right side of the screen - and once you have fired off a shot at all of them to kill them, another group of eight more Type 1 enemies shall come flying towards you from the right side of the screen (while firing projectiles at you). Once you've fired a shot at each of them to kill them, the twelfth and sixteenth ones will leave two more blue device packs behind; once you've collected them another group of eight more Type 5 enemies will come flying towards you from the right side of the screen, while firing beams at you. Once you have fired a shot at all of these to kill them, the tenth and fourteenth ones will leave two final blue device packs behind - and once you have collected them, your (or both) Mega Blast will stop moving as the round's mini-boss (which is Chack'n, out of 1983's Chack'n Pop!) comes down into view from the top of the screen, then starts hovering up and down while spitting projectiles at them. Once you've fired enough shots at this formerly heroic Taito character to defeat him, he shall explode and fall off the bottom of the screen; your (or both) Mega Blast will then undergo a fifth dramatic increase in speed (which, for a fifth time, means that a boss battle is approaching, and for what happens to be the second time in the game, just after defeating the mini-boss as well) as the following text gets displayed on the screen:
"Flying Medusa" (filename: Three Head) will then fly into view, from the right side of the screen; it attacks by spitting flames at you from its three dragon-like heads while following you around the screen (which means you shall have to keep moving so it does not trap you), and once you have fired enough shots at each of its heads (and their necks) to deactivate them it will explode and fall off the bottom of the screen. Your (or both) Mega Blast will then fly off the right side of the screen as the text "ROUND 5 OVER. NICE PLAY! GO TO NEXT ROUND." is displayed on the screen, and proceed to Round 6.