The first fly in the game, found at Tadpole Pond. In Tadpole Pond, there will be some fellow tadpoles. If you bump into most of them, you should get this fly.

The second level of the game, Trout Tributary, contains the rare Gold Fly. In this level, there will be some golden sparkles instead of regular purple ones. Grab all of these to obtain the Gold Fly. Not sure where to look? Try looking under objects.

Turtle Pipes, home of Walt the Turtle is also home to a rare creature known as the Beat Fly. This fly can be yours for the small price of landing every jump in the level.

Chiptune Lagoon has many strange creatures, but none as mysterious as the Bamboo Fly. This fly can only be seen if you manage to hit every bamboo pole in the level.

Mightnight Bayou contains many mosquitoes which are natural predators to the endangered Pesky Fly. This fly will only come out of hiding if all of the mosquitoes in the level are hit. If you didn't already know, you can hit the mosquitoes on the jumps by hitting the attack button.

Heh, booty... uh I mean... The Booty Fly. You can get this fly by hitting the "X" on the treasure map in this level. You may also have to hit the gold. Not to sure about this one, I kinda got it on accident.

EDIT: The Booty Fly is obtained should you hit 3 unique jumps in the level, Which are:
-The Gold Doubloon during the first calm section
-The 'X' on the treasure map
-The Golden Tooth of the Skull

Thanks to Dat Guy? Why? for giving me this info!

One of the few creatures to survive the harsh temperatures of Snowfall Lake is the famine fly. This fly can be obtained by not grabbing a single piece of food the entire level. Be careful, some of the jumps have pieces of food that are hidden by the snow.

The Gusty Rapids contains many rare treasures, but none as rare as the Jewel Fly. You will unlock the power to own this fly by grabbing every jewel in the stage, which are obtained by hitting jumps.

The delicate Glass Fly lives a secluded life in the dangerous Pihranna Jungle. This fly is not easily impressed, and will only present itself if one can survive these waters without taking ANY damage.

Few creatures can survive the harsh climate of Thunder Creek, such as the snails and the elusive Bone Fly. This fly can be added to your collection by grabbing all of the bubbles that are located inside of the skulls.

Get your steamsaltys, because you are going to have to brave the salt waters for the Salty Fly. This fly is obtained by not hitting a single jump in the stage and staying in the ocean the entire level. Keep grabbing food and keeping an eye on that life bar.

Victim of the crash of ELE-94, the Allegro Fly still resides at the crash site. To get this fly, you will need to unleash the speedrunner inside of every gamer and beat the last phase of the boss fight as quick as possible. As quick as possible means that you will have to beat the song without it looping.

The Maestro Fly is said to be the rarest creature on the planet. To get this fly, you must conquer Concerto Mode. After doing this, you BETTER SEE WHAT ETUDE HAS TO SAY ABOUT IT'S MAGNIFICENT FLAVOR.

As you can probably tell, this guide was done in about ten minutes. If you have any suggestions, questions, feedback, or things that I missed, please tell me. Good luck on 100%!