Here is the full list of all 30 Sheepy: A Short Adventure achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
You finished the game without dying.
You beat the game in 45 minutes.
You beat the game in 30 minutes.
You lit all the crystals!
The last one?
Wait, another Sheepy?
Almost done!
You listened to all the tapes.
You have activated the 6 levers.
The third one!
It feels nostalgic here.
You finished the game.
... is awaiting you.
I know this place!
But now you can fly.
You showed Patches who's the boss.
You can do it!
Run as fast as you can.
GOTTA GO FAST
Archaeologist is a dangerous job.
BABY, RIGHT 'ROUND
Such an engineer.
The second one!
"Your estimated wait time is forever."
You made a new friend!
"Taking You Higher"
Something happened here...
The first one!
...but no you can't, because you're a sheep.
You're a smart one, aren't you ?