The game is almost done. I added missions, daily challenge:
And now I'm left with sound effects, Google Play integration, and maybe a couple more bosses. Here are the bosses I have so far:
1. Borg: releases drones 1-by-1
2. W: releases 6 drones at a time in 2-2-2 formation
3. K: does not move. Releases two constant waves waves of drones going sideways
4. Snake: looks and moves like a snake, releases drones from its head
5. Splitter: splits into two smaller drones when hit (can be hit 4 times, resulting in 8 drones at the end)
6. Evader: teleports to a different location each time you hit it
7. Blower: grows when hit, gets smaller when it releases drones. Turns into drone at the end.
8. Invisible: gets invisible and only shows up when releasing drones
9. Windmill: rotates and releases drones, when destroyed releases a lot of spiked mines
10. Boss of the bosses: releases Borg bosses (which in turn release regular drones)
11. Catcher: releases 8 drones at a time in 3-2-3 formation
12. Twins: when one of them loses energy, the other increases. Bigger one tries to protect the other.
13. Rotator: has vunerable core and hard protective shell. You have to wait until it rotates the vunerable part downwards
14. Mega boss: the only boss that does not release drones, but goes downward itself and has loads of energy
This means that bosses do not repeat until wave 150. It's hard to get that far, but I did manage wave 178 and 199 so far, so I'd like to add unique bosses up to level 200 at least.
If you played the .jar file and have some boss ideas, please let me know.