I thought about it and I made this :
All the barriers must be destroyed in order to free the apple core from the bubble.
When different barriers are destroyed it will shoot 2, 4, 6, 8, 10, 12, 14, 16 I* respectively.
The lvl 4 barriers will shoot randomly
& There would be 4 anomalies facing to the center
*I = red Ions
Thanks for reading