Here is the full list of all 22 1HEART achievements.
Make 5000 mouse clicks
Find all hidden hearts in the game
Play 1Heart for more then three hours
Complete the game
Get to basement without hints
Solve hidden object puzzle without hint
Listen to seven hidden tracks
Check all console commands
Check "The Pirate Bay" site in computer console
Make 2000 mouse clicks
Find dissecting room in less then 2 hours
Play 1Heart for one hour
Listen to four hidden tracks
Find half of the hidden hearts
Open door leading to the church basement
Destroy all possible crates
Kill sheep
Enter the church
Solve ancient ornament riddle
Pass the river
Make 200 mouse clicks
Complete the tutorial