The elf said so because he could sense the dreadful terror of Sheyan's 'old friend'.
The creature hadn't even appeared and was merely a phantom residing beneath the forbidden terrain of the waters. Yet, it brought along an incredibly crushing pressure.
All hostilities would fade in the face of such a domineering beast! No wonder those savage aquatic beasts had fled in frenzy.
Therefore, attempting a spirit link would be extremely dangerous especially if the disparity of strength was tremendous. A wild beast may not be in the mood to care about one, yet if one purposefully disturbs it, it may fly into a rampage and devour one's spirit!
It was like an annoying mosquito bugging on. The beast would never endure such annoyance and the consequence may even be an internal rupture of one's mind.