Here is the full list of all 22 InfiniPicross achievements.
100 Solved
50 Solved
25 Solved
Create a Theme
Reset a Filled Grid
99x50 (or 50x99) or Bigger Completed
Use The Workshop
A Certain Familiarity
Set a Seed
10 Continues in a Row
5 Continues in a Row
10 Solved
One Continue
50x50 or Bigger Completed
Change Theme
5 Solved
25x25 or Bigger Completed
15x15 or Bigger Completed
10x10 or Bigger Completed
5x5 or Bigger Completed
First Solve
3x3 or Bigger Completed