I have only played with the Slime so far, so I do not know how the interaction with other unlocks work with the silent boss.

My understanding: At the start of each turn, a fake image of the silent appears. The location of the image and the silent is random. The first time you play an attack, the image disappears.

Issue: RNG targeting. Your random target and slimelings will hit at random. While the double is there, it make sense that they are randomly selecting the double and the silent. However, after you have played an attack, and popped the image. The RNG targeting is still hopping back and forth between an empty space and the silent, which results in the fight taking a lot longer than it needs to be.

Lore wise, that could make sense as the slimings and the random goop spell may still be "confused" as to where the silent is. But that being the case, for the slimlings should only "see" the image during their first attacks at the start of the round. After which, the image would be gone fore them.

How I imagine it should be, is:
1) Fade becomes active, randomize location of silent and image.
2) While the image is active, stats are hidden.
3) Image fakes stats, so no indication which of the two are hit. Additionally, minion status and no other kind of rewards for hitting the image. (No consume, no life leach, et cetera.)
4) When an attack is played: resolve all effects, then image "fades" similar to darkling slimes.
5) Faded image can no longer be targeted, similar to darklings.

(No experience modding, but an idea.) Perhaps to help facilitate this transition from the image being faded, copy and modify the life link. While silent is alive, reform at the end of turn, can not be consumed.. When either takes attack damage, image fades. Shuffle monster # designation at start of players turn.

Side note, I was occasionally seeing the RNG targeting Neow sometimes during the Hero Fight while Neow was providing backup. Resulted in my assuming that I would go directly into fighting him once I was done consuming all the heroes.