A 4x4x4 solid can be filled with four copies of a hexacube and five copies of a octacube. Here we restrict the hexacube to be a solid hexomino and the octacube to be a solid octomino.

Below is a catalog of the hexomino/octomino pairs for which solutions exist. The catalog links to solution drawings whenever there are three or fewer solutions. For example, to see the two solutions for four U-hexacubes and five 8fr-octacubes, click the solution drawings link. In the bottom half of the linked window you will see a frame for each solution. Within the frame you can click on the next (or previous) link to add (or remove) a piece from the drawing.
1: 4 P-hexacubes, 5 8ep-octacubes
1 solution

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solution drawings
2: 4 P-hexacubes, 5 8es-octacubes
1 solution

5×
solution drawings
3: 4 Short N-hexacubes, 5 8en-octacubes
1 solution

5×
solution drawings
4: 4 V-hexacubes, 5 8fk-octacubes
1 solution

5×
solution drawings
5: 4 V-hexacubes, 5 8gg-octacubes
1 solution

5×
solution drawings
6: 4 J-hexacubes, 5 8gu-octacubes
2 solutions

5×
solution drawings
7: 4 J-hexacubes, 5 8gv-octacubes
2 solutions

5×
solution drawings
8: 4 U-hexacubes, 5 8fr-octacubes
2 solutions

5×
solution drawings
9: 4 O-hexacubes, 5 8er-octacubes
4 solutions

5×
10: 4 Q-hexacubes, 5 8gw-octacubes
4 solutions

5×
11: 4 Q-hexacubes, 5 8hy-octacubes
4 solutions

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12: 4 M-hexacubes, 5 8ed-octacubes
5 solutions

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13: 4 Hi4-hexacubes, 5 8ed-octacubes
6 solutions

5×
14: 4 A-hexacubes, 5 8ed-octacubes
many solutions

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15: 4 C-hexacubes, 5 8ed-octacubes
many solutions

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16: 4 C-hexacubes, 5 8er-octacubes
many solutions

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17: 4 D-hexacubes, 5 8ed-octacubes
many solutions

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18: 4 E-hexacubes, 5 8fk-octacubes
many solutions

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19: 4 J-hexacubes, 5 8ed-octacubes
many solutions

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20: 4 O-hexacubes, 5 8ed-octacubes
many solutions

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21: 4 O-hexacubes, 5 8en-octacubes
many solutions

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22: 4 O-hexacubes, 5 8fk-octacubes
many solutions

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23: 4 O-hexacubes, 5 8gu-octacubes
many solutions

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24: 4 O-hexacubes, 5 8gv-octacubes
many solutions

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25: 4 P-hexacubes, 5 8ed-octacubes
many solutions

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26: 4 P-hexacubes, 5 8gu-octacubes
many solutions

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27: 4 P-hexacubes, 5 8gv-octacubes
many solutions

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28: 4 P-hexacubes, 5 8ld-octacubes
many solutions

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29: 4 Q-hexacubes, 5 8ed-octacubes
many solutions

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30: 4 Q-hexacubes, 5 8fk-octacubes
many solutions

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31: 4 R-hexacubes, 5 8ed-octacubes
many solutions

5×
32: 4 R-hexacubes, 5 8fk-octacubes
many solutions

5×
33: 4 Short T-hexacubes, 5 8ed-octacubes
many solutions

5×
34: 4 Short Z-hexacubes, 5 8ed-octacubes
many solutions

5×
35: 4 U-hexacubes, 5 8ed-octacubes
many solutions

5×
36: 4 U-hexacubes, 5 8gv-octacubes
many solutions

5×
37: 4 V-hexacubes, 5 8ed-octacubes
many solutions

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