Here is the full list of all 22 Pixel Puzzle Makeout League achievements.
Couldn't resist
Unlocked all special themes
Completed the Puzzle Maze
Remade the world / Set off on your own
Remembered what part she is
Found true love
Became whole with Piecea
Solved 200 pixel puzzles
Climbed a mountain with Piecea
Became partners with Chess
Found the truth with Crossword
Saved Sudoku
Made a costly mistake
Solved 100 pixel puzzles
Explored the digital realm
Survived an encounter with the Villain
Tried something new with Sudoku
Learned about Crossword's past
Went on a sneaking mission with Chess
Got to know a member of the Puzzle League
Let the timer run out
Escaped the Villain's clutches