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 beat the game in 45 minutes.
You beat the game in 30 minutes.
The second one!
Wait, another Sheepy?
Almost done!
You listened to all the tapes.
The third one!
You have activated the 6 levers.
You're a smart one, aren't you ?
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.
Archaeologist is a dangerous job.
GOTTA GO FAST
It feels nostalgic here.
BABY, RIGHT 'ROUND
Such an engineer.
"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.
The last one?
You lit all the crystals!
You finished the game without dying.