This Hard did not require any guessing either :

javascript:for i1 i9 i for j1 j9 j if gridij.value ClearTinySquaresi,jfor i1 i9 i for j1 j9 j if gridij.value ! var tmp_value gridij.valuefor k1 k9 k for l1 l9 l if gridkl.value if Math.ceili/3 Math.ceilk/3 Math.ceilj/3 Math.ceill/3 i k j l gridklminitmp_value -1for i1 i9 i for j1 j9 j if gridij.value for k1 k9 k if gridijminik ! -1 gridijminik 1 for i1 i9 i for j1 j9 j if gridij.value for k1 k9 k if gridijminik ! 1 gridijminik 0PopulatePuzzlegridvoid0

first time wifi for 3 weeks but think Ill catch up later, too much fun to be had in Majorca

A hidden pais broke it wide open.

Pair....fingers are fat today..