This is easy to understand.
Just like they are both water.
The water of a small stream encounters that of a lake.
When the two meet, the greater probability is that the stream's water merges into the lake, becoming thoroughly fused!
And Sword Spirits born from the Sword Realm have essentially similar natures.
If two Sword Spirits converge.
There's a high probability that the weaker one will be unconsciously devoured by the stronger one.
Sometimes, the stronger one can't even control themselves, because this is the natural law of the world, unless the two Sword Spirits are apart, not together day and night, but if they are together day in and day out, over time, strange merging and combining phenomena are sure to occur.
And perhaps for this reason, Jian Yue abandoned the Emperor's Sword, which was such an unparalleled Divine Weapon.
After all.
Jian Yue is not a person; he is a Sword Spirit.
