There are no permanently missable achievements. Once you've see the credits, the game will quit and you'll be set back to either right after solving the Mayor's request or during your last save. You can get everything in one playthrough.

These are story achievements that are impossible to miss and you get them by simply beating the game:

- Hello Yuri!
- Drip Acquired
- Apples to Apples
- YeeHaw!
- Pick-me-up
- Mushrooms Afungus
- CONNECTING...
- Establishing Community
- Cherry on top
- What is this, some kinda Re:Fresh?

The Final Gap
You get this by going to the Cliff Section after fulfilling every request except the Mayor's. It'll prompt you to repair the bridge. If you do so, you get the achievement.

Yo
At the cliffs you can find a cat hiding behind the mountains, on ground level. Basically once you enter the cliff-section just walk at ground level around the mountains and you'll find her easily.

Cell-ebrate!
You get this achievement by getting the four cell fragments. You do not need to collect all Solar Cells, you just need the four fragments. Two are in the forest, two are the cliffs. You can find their exact locations in the twitch clips below:

Cell Fragment #1 (Forest)
https://clips.twitch.tv/EnergeticImpartialAnteaterPJSugar-ITfAZ1kX07Xufubg

Cell Fragment #2 (Forest)
https://clips.twitch.tv/CourteousDarkPrariedogDatBoi-8nRNiHfHPuJihCsH

Cell Fragment #3 (Cliffs)
https://clips.twitch.tv/SpoopyReliableSangSoonerLater-5aRwEksqIkiWZW-q

Cell Fragment #4 (Cliffs)
https://clips.twitch.tv/BoldPunchyWheelMrDestructoid-I_wDCWa_9sTG1CRX

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