Birthday celebration puzzle! (LVL 3+, 6 hours left) (Bigger Hints Added)

It's It was my birthday today, so i made a GA (non-bundled).
But despite being a fancy rat, i still have bad genes of my greedy&sneaky predecessors, and will not give this gift easily.
Here is two-step puzzle for you:
First, you have to guess the game i am giving away.
Second, find a link to this GA.

Without further delay... Grab a puzzle

HINTS
Step 1:
You can meet my species a lot in this game!
This game has a sequel, which is standing quite high in community wishlist

Step 2:
Need to play with some properties to see what is hidden.
If you don't know how to "play" with properties of image, there is some sites that can help you detect changes in images

P.S.
I totally recommend everyone to check out this guide It contains a lot of useful information for puzzle solvers (and creators) on SG!