The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  X  2  1  1  1 X^2  1  1
 0  X  0 X^2+X X^2 X^2+X+2 X^2+2  X  0 X^2+X X^2+X X+2  X X^2+X  X  2 X^2 X^2+2  2 X^2+X+2 X^2+X+2
 0  0 X^2+2  0 X^2 X^2  2 X^2  2  2 X^2 X^2+2  0  0 X^2 X^2 X^2 X^2+2 X^2  0 X^2
 0  0  0  2  2  0  2  2  0  0  2  0  2  0  2  0  0  0  2  0  2

generates a code of length 21 over Z4[X]/(X^3+2,2X) who´s minimum homogenous weight is 18.

Homogenous weight enumerator: w(x)=1x^0+81x^18+56x^19+257x^20+272x^21+210x^22+56x^23+77x^24+13x^26+1x^36

The gray image is a code over GF(2) with n=168, k=10 and d=72.
This code was found by Heurico 1.16 in 0.015 seconds.