They are told upon arriving at Mercy Island that they are somehow "special". That they and they alone are "destined" to become the next ruler of the Rogue Isles and even take the place of Lord Recluse. The supposed "Path to Destiny" is one that they are told must be done in secret, and that only the Fateweavers can show them this path.
It is all a lie, though.
The truth is that these villains are set up to fail. The deception is Lord Recluce's idea to get compliance from the other villains and to get them to do the bidding of Arachnos.