The generator matrix

 1  0  1  1  1 X+2  1  1  2  1  1  2  1  1  1  1  0  2  1  1  0
 0  1  1  0 X+3  1  X X+3  1 X+2  1  1  2 X+3  0  3  1  1 X+3  0  1
 0  0  X  0 X+2  0  0  2  2  0  2  X  X X+2 X+2 X+2  X  0  2 X+2 X+2
 0  0  0  X  0  0 X+2 X+2  X  2 X+2  2  2  0  X X+2  X  X  0  X  0
 0  0  0  0  2  0  2  0  2  0  0  2  0  2  0  2  2  2  0  0  0
 0  0  0  0  0  2  0  0  0  2  2  0  0  2  2  2  2  2  0  0  0

generates a code of length 21 over Z4[X]/(X^2+2,2X) who´s minimum homogenous weight is 16.

Homogenous weight enumerator: w(x)=1x^0+118x^16+72x^17+406x^18+384x^19+781x^20+624x^21+738x^22+384x^23+389x^24+72x^25+98x^26+23x^28+6x^30

The gray image is a code over GF(2) with n=84, k=12 and d=32.
This code was found by Heurico 1.16 in 0.178 seconds.