The generator matrix

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

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+205x^16+276x^17+746x^18+836x^19+1351x^20+1320x^21+1398x^22+936x^23+685x^24+196x^25+190x^26+20x^27+29x^28+2x^30+1x^32

The gray image is a code over GF(2) with n=84, k=13 and d=32.
This code was found by Heurico 1.16 in 1.61 seconds.