Was it unusual to combine battle puppets?
Not really.
The heritage in the Galaxy Universe had all kinds of methods regarding the combination of battle puppets.
Many combinations of war puppets were quite impressive.
Although the battle puppet Han Muye just refined was a level five combination and showed the combat power of a quasi-sage level, which was indeed rare, it wasn't what those divine-level refiners valued.
Although they were unable to refine a battle puppet with the combat power of a sage-level battle puppet, they knew that such a battle puppet had a drawback.
After the battle puppets combined to become sage-level, the original level five puppet masters would no longer be able to control them.
It required a sage-level puppet master to control them.
In this way, it was not as effective as a sage-level puppet master taking action and controlling his own battle puppet.