Choke
With Divided We Stand, not only could he infiltrate several places simultaneously, but he could also share information across his duplications in real time.
However, although he had the mind of a divine immortal, Feng Luotian had never used the mind-splitting technique before, so this kind of delicate control over several bodies would take a heavy toll on his mind. Right now, he could only split into five bodies at the maximum.
He would require some time to get used to this ability before he could split into more figures in the future.
The reason he switched out Blood Steel was because it was the best that both abilities would not stay on him at the same time as their concepts contradicted each other.
Divided We Stand focused on cautiousness because their health had been drastically decreased by the split. One attack could make a genocide out of him.