Violet Detector's Danmaku Dream 4 from Nightmare Diary starts with an attack that is very much like your shottype from the game. If you decide not to deal any damage to enemy Sumireko, the pattern will not change the whole fight.
However, if you start shooting enemy Sumireko, the pattern will change throughout the fight, although there aren't any HP markers to hint where this change will occur. The second phase of the attack consists of many orange and blue amulets, but they seem to be shot in two different ways, as seen as in the gif above.
In the third phase, the amulets are being shot at a lower speed, but Sumireko starts teleporting around. The fourth phase additionally has fireballs.











