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