Well done on making your first game.
Just a little feedback,
Game has nice feel to it, with 2 nice cheery characters. The platform tile, background colour and replay button look good.
Found the game quite difficult though, do you really need so many cogs?
Though the fly mechanic is fun, maybe it's overused though - a cool feature would be a fly meter so that
when it reaches 0 a timer is set for 5 seconds or so as it recharges - Just one idea out of many to get some
more strategy in the game - Or maybe tweak the gravity settings with a timer so that the characters start to fall
after a time value - just experiment with the physics and see what you can come up with because there isn't much control of the flying at the moment,
though floating element is quite fun so you might end up keeping one way or another.
You could possibly activate the gravity rules for flying on a double jump when meter == 0 no flying, and mix the levels up a bit with
platforms and cogs and anything else you can think of.
Also you might want to think about how Bloin & Leg will have different abilities or have to work together to complete a level,
I tried to play in Uberschizoid mode(http://en.wikipedia.org/wiki/Schizoid_(video_game
) didn't help me any.
To pick up what BobtheLawyer was saying about collisions, they do seem a little off here and there, are your
collisions set to the default which would be box or square - for the cogs a circle collision mesh might be better.
for optimization of collisions check this article out/it is for construct2 but I'm sure the tips will work for Stencyl2 https://www.scirra.com/blog/ashley/6/collision-cell-optimisation-in-r155
not sure if you need this kind of optimization the framerate only dropped a few times for me, still it's a good read.