Cast Rescue the Foal by paying ({1} magic symbol) ({W} magic symbol) , blinking Fiend Hunter and exiling Rescue the Foal.
When Fiend Hunter enters the battlefield, its first ability and Preston trigger.
Resolve the Fiend Hunter trigger, exiling Abdel Adrian.
Resolve the Preston trigger, creating a copy of Fiend Hunter that is a 0/1 Illusion.
When the token Fiend Hunter enters the battlefield, its first ability triggers, exiling the nontoken Fiend Hunter until the token Fiend Hunter leaves the battlefield.
When the nontoken Fiend Hunter leaves the battlefield, its second ability triggers, returning Abdel Adrian from exile to the battlefield.
When Abdel Adrian enters the battlefield, it and Preston trigger.
Resolve the Preston trigger, creating a token copy of Abdel Adrian that is a 0/1 Illusion.
Put the token Abdel Adrian into your graveyard due to the legend rule.
The token Abdel Adrian's enters-the-battlefield ability triggers, choose not to exile a permanent.
Resolve the Abdel Adrian trigger, exiling the token Fiend Hunter and creating a 1/1 Soldier creature token.
When the token Fiend Hunter leaves the battlefield, it triggers, returning the nontoken Fiend Hunter from exile to the battlefield.