Completing all 10 boss levels from Zombie Fish Tank.

Here's a list for each boss:

0:00 Scientist Zombie Aquarium
1:40 Mechanical Fish Toilet of Doom
2:43 Booger Fish Pipes of Fury
4:52 Level Walkthrough Waste Waters
7:36 Hiding Snake Mutant River
9:00 Chain Gun Freak Wreck
10:54 Level Walkthrough Alien Tempe
14:07 Jaws Boat Waterfall Bay
15:40 Green Eye Monster Guts
17:10 Alien Base Storm of Destruction

Hope this helps guys.