The generator matrix

 1  1  1  1  1  1  1  1  2  2  2  2  2  2  2  1  1  2  2  2  1
 0  2  0  0  0  2  6  2  0  0  4  2  6  2  6  2  0  6  4  4  0
 0  0  2  0  2  2  6  0  0  2  2  2  6  4  0  0  2  0  2  4  0
 0  0  0  2  2  0  6  2  2  2  0  0  6  2  0  2  6  4  0  4  0
 0  0  0  0  4  0  0  0  0  0  0  0  4  4  4  0  0  4  4  0  0
 0  0  0  0  0  4  0  0  0  0  4  0  0  4  4  0  4  4  4  4  0
 0  0  0  0  0  0  4  0  0  0  4  4  4  4  4  0  0  0  0  0  0
 0  0  0  0  0  0  0  4  0  0  4  4  0  0  4  0  4  0  0  4  0
 0  0  0  0  0  0  0  0  4  0  4  0  4  0  4  4  4  0  4  4  0
 0  0  0  0  0  0  0  0  0  4  4  4  4  0  0  4  4  4  0  4  0

generates a code of length 21 over Z8 who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+132x^12+116x^13+296x^14+368x^15+1016x^16+1544x^17+2506x^18+2984x^19+4256x^20+6384x^21+4200x^22+2920x^23+2508x^24+1592x^25+1084x^26+376x^27+268x^28+92x^29+96x^30+8x^31+11x^32+10x^34

The gray image is a code over GF(2) with n=84, k=15 and d=24.
This code was found by Heurico 1.16 in 5.41 seconds.