Hidden Kill Hall's most formidable four assassins, among them Wind Monarch and Lord Lei, had already overwhelmed Fang Lin with Fire King's prowess, at which point he had narrowly escaped death by Fire King's hands.
A single Fire King was a significant threat to Qian Country, and should Wind Monarch and Lord Lei also arrive, Hidden Kill Hall must be planning a significant operation in Qian Country; otherwise, they would not deploy three such powerful experts simultaneously.
However, Gu Hanshan only shared this much and did not disclose what Hidden Kill Hall intended to do in Qian Country, which left Fang Lin quite uneasy.
Nevertheless, Fang Lin was not overly worried, as Purple Mist Sect housed an elder, Sword Head, whose presence he believed would prevent Hidden Kill Hall from any major undertakings. With Sword Head's capabilities, he should be able to handle the four great assassins of Hidden Kill Hall.