I was able to do this hueforge with only 4 colors. The model was sliced in a way where the filaments would swap at appropriate layers, but if you don't have an AMS, I include the layer swaps below. Make sure to have layer height at 0.08mm, and initial layer height at 0.16mm; also make sure sparse infill density is at 100%.

Filaments Used:

Inland Pla Matte Black

Inland Pla Matte White

Inland Pla Matte Grey

Inland Pla Matte Army Beige

Layer Swaps:

• Start with Black
• Layer 7 (0.64) swap to grey
• Layer 8 (0.72) swap back to black
• Layer 10 (0.88) swap to white
• Layer 11 (0.96) swap to brown
• Layer 12 (1.04) swap to black
• Layer 13 (1.12) swap to brown again
• Layer 19 (1.60) finish with white