Conversation so far:
Where did Migration Period art originate?
Migration Period art denotes the artwork of the Germanic peoples during the Migration period. It includes the Germanic tribes on the continent and in the British Isles.
Did the style of Migration Period art migrate at all?
In the 3rd century, the Roman Empire army was becoming increasingly Germanic, so when Huns pushed German tribes westward, they spilled across the Empire's borders and began to settle there.
Did the Migration Period artwork travel with the Huns?
The polychrome style originated with the Goths who had settled in the Black Sea area. This style was also popular with the Huns.

Question: What did this poychrome style look like?
Self-contained rewrite: What did the Migration Period poychrome art style look like?