Finally completed the 85% challenge. Heres how mine ended up looking https://imgur.com/G6nCEaE
Heres a hint, you need to complete the challenges found in the title screen to get extra medals. I'd say you can get probably 25-30% easily from there.
Good luck!
Game is way too big, at a certain point it just becomes too easy, and I have no desire to spend the next 3-4 hours going through every level one by one just to get the badge.
For people with difficulty getting your happiness up like I had, the Living Research Center building is unlocked after researching microchips and bumped me up 6 entire points which was just enough to get the 80 happiness needed. You should focus on upgrading asap.
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