The generator matrix

 1  0  0  0  1  1  1  0  1  1  2  1  1  0  2  0  0  2  0  2  1
 0  1  0  0  0  1  1  1  0  0  0  3  3  1  1  1  1  2  0  0  0
 0  0  1  0  1  1  0  1  0  1  1  1  0  2  1  0  1  2  1  0  0
 0  0  0  1  1  0  1  1  1  0  1  1  2  1  0  0  1  1  0  0  0
 0  0  0  0  2  0  0  0  0  0  0  0  2  2  2  0  2  0  0  2  0
 0  0  0  0  0  2  0  0  0  0  2  0  2  2  0  0  2  0  2  0  0
 0  0  0  0  0  0  2  0  0  0  2  0  2  0  2  2  0  2  2  2  0
 0  0  0  0  0  0  0  2  0  0  2  2  2  2  2  2  2  2  0  2  0
 0  0  0  0  0  0  0  0  2  0  2  2  0  2  0  0  0  2  0  2  0
 0  0  0  0  0  0  0  0  0  2  2  2  0  0  2  0  2  2  2  2  0

generates a code of length 21 over Z4 who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+136x^12+114x^13+290x^14+306x^15+752x^16+1040x^17+1240x^18+1504x^19+1696x^20+2276x^21+1636x^22+1460x^23+1236x^24+1088x^25+816x^26+304x^27+264x^28+90x^29+106x^30+10x^31+11x^32+8x^34

The gray image is a code over GF(2) with n=42, k=14 and d=12.
This code was found by Heurico 1.16 in 6.19 seconds.