About the matter of the "fake Koslin".
Han Dong had doubts from the moment they met.
Involving the clown's hidden events, how the three people managed to pass through unharmed was obviously unusual... It's not that Han Dong didn't trust in his teammates' strengths.
After all, Han Dong himself was injured while carrying out a side task.
He was shot multiple times in the lower body by a bullet and invaded by a swarm of parasites...
Upon their meeting, Han Dong swept his [The Eye] across the three of them.
There was nothing wrong with Cass and Sophia.
But he found a stream of red energy swirling inside Koslin.
In the subsequent clue discussion session, Han Dong observed Koslin many times.
He confirmed that this red energy was not accidentally contaminated by Koslin, but 'brought along'... Coupling this with Koslin's deliberate behaviour of actively asking for a camera later on, Han Dong basically confirmed his identity.
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Quiet night.
