How do you count the range to a potential target of Kouhun Infestation?
You count range just as you would count for any special ability — diagonals count as 2 squares, but squares containing low objects and difficult terrain do not. You have to count around walls as normal, even though you don’t need line of sight to the target. The range is measured along the shortest path to the target. See the glossary definition of range for more details.