The goal is to get the fish from where it starts to the square with the yellow X using the arrows. This requires a lot of planning ahead, so read to the end of this hint for a map.
Hint 3
The gimmick is that your green fish has to pass through many gates, and it can only unlock the gates that match its current characteristics. The green fish can only unlock gates that show either a green square (meaning anything green can go here), an outline of a fish (meaning any color fish can pass), or a green fish (meaning only green fish get through).
Hint 4
To change your piece's characteristics, you need to go through the large color blocks (to change its color) and the large animal outlines (to change its species).
Hint 5
So if you need to go through a red squid gate and your piece is currently a blue turtle, you'll need to send your piece through red and squid blocks before you can go through that red squid gate. See?
Hint 6
If you're having trouble making progress, try planning from the end backwards. This will require lots of planning, mapping, and painstaking thinking ahead --
Hint 7
-- all of which I hate and stink at, so here's a map you can just follow instead of puzzling it out. In this map, the path you need to follow changes colors as your piece changes color; hopefully, that will help you keep track of where you're supposed to go.
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