"We can share no details on this one, but your target is a breeder called Mazarine. You should be able to find her in the Cave of Endergate."
How to Complete
Note those are all water creatures, so Air monsters are your best bet. It's also a good idea to take monsters that can attack multiple targets at once and kill the last 2 or 3 Don Penguinis before killing ever other monster to save yourself some losses from a lone penguins Last Stand attack. Also - expect those turtles to explode.
2483 silver (exact ammount may vary depending on level)