How do I properly run Lord Syuul's villain action #2?

My players and their PCs are going to fight Lord Syuul soon. This is his villain action #2:
>Phantom Pain, Psionic, Self
>Effect: Lord Syuul becomes invisible, can teleport up to 10 squares, and projects an illusory double within 10 squares. The double can’t move or act, but Lord Syuul can use psionic abilities as if he were in its square. Whenever a creature touches or damages the double with a melee strike, they take 10 psychic damage. If Lord Syuul takes damage, his invisibility ends and the double disappears.

I see an issue here. Invisible does not mean automatically hidden. Lord Syuul still has to manually, on his turn, use the Hide maneuver. Heroes, p. 276:
>Invisible creatures always have concealment from other creatures. If an invisible creature isn’t hidden, they can still be targeted by abilities. The test made to find a hidden creature who is invisible takes a bane.

So in that regard, the jig might be immediately up. The PCs instantly know that the real Lord Syuul has already teleported away and gone invisible, so why bother touching or damaging the double?

Let us say we integrate a Hide into the villain action (or just have Lord Syuul Hide ASAP), and declare that the PCs are ignorant of the trickery. Presumably, a PC taking psychic damage from the double alerts them that something is wrong, but what happens if the next PC to act uses a non-melee-strike ability on the double? Does nothing happen? Does that alert the PCs?

I am having trouble figuring this out. Would it be fine if I were to swap out this villain action for a villain action from the voiceless talker evolutionist? The Monsters book, p. 25, says to "use stat blocks as written," so I am wary of making such a modification.

How do I properly run Lord Syuul's villain action #2?

My players and their PCs are going to fight Lord Syuul soon. This is his villain action #2:
>Phantom Pain, Psionic, Self
>Effect: Lord Syuul becomes invisible, can teleport up to 10 squares, and projects an illusory double within 10 squares. The double can’t move or act, but Lord Syuul can use psionic abilities as if he were in its square. Whenever a creature touches or damages the double with a melee strike, they take 10 psychic damage. If Lord Syuul takes damage, his invisibility ends and the double disappears.

I see an issue here. Invisible does not mean automatically hidden. Lord Syuul still has to manually, on his turn, use the Hide maneuver.
>Invisible creatures always have concealment from other creatures. If an invisible creature isn’t hidden, they can still be targeted by abilities. The test made to find a hidden creature who is invisible takes a bane.

So in that regard, the jig might be immediately up. The PCs instantly know that the real Lord Syuul has already teleported away and gone invisible, so why bother touching or damaging the double?

Let us say we integrate a Hide into the villain action (or just have Lord Syuul Hide ASAP), and declare that the PCs are ignorant of the trickery. Presumably, a PC taking psychic damage from the double alerts them that something is wrong, but what happens if the next PC to act uses a non-melee-strike ability on the double? Does nothing happen? Does that alert the PCs?

I am having trouble figuring this out. Would it be fine if I were to swap out this villain action for a villain action from the voiceless talker evolutionist? The Monsters book, p. 25, says to "use stat blocks as written," so I am wary of making such a modification.

How do I properly run Lord Syuul's villain action #2?

My players and their PCs are going to fight Lord Syuul soon. This is his villain action #2:
>Phantom Pain, Psionic, Self
>Effect: Lord Syuul becomes invisible, can teleport up to 10 squares, and projects an illusory double within 10 squares. The double can’t move or act, but Lord Syuul can use psionic abilities as if he were in its square. Whenever a creature touches or damages the double with a melee strike, they take 10 psychic damage. If Lord Syuul takes damage, his invisibility ends and the double disappears.

I see two issues here. Firstly, invisible does not mean automatically hidden. Lord Syuul still has to manually, on his turn, use the Hide maneuver.
>Invisible creatures always have concealment from other creatures. If an invisible creature isn’t hidden, they can still be targeted by abilities. The test made to find a hidden creature who is invisible takes a bane.

So in that regard, the jig might be immediately up. The PCs instantly know that the real Lord Syuul has already teleported away and gone invisible, so why bother touching or damaging the double?

Let us say we integrate a Hide into the villain action, and declare that the PCs are ignorant of the trickery. Presumably, a PC taking psychic damage from the double alerts them that something is wrong, but what happens if the next PC to act uses a non-melee-strike ability on the double? Does nothing happen? Does that alert the PCs?

I am having trouble figuring this out. Would it be fine if I were to swap out this villain action for a villain action from the voiceless talker evolutionist? The Monsters book, p. 25, says to "use stat blocks as written," so I am wary of making such a modification.