Suggestions by @cw1234

Jamie Campbell Bower

as New Villains in Gravity Falls: Dipper and Mabel Return

Rami Malek

as New Villains in Gravity Falls: Dipper and Mabel Return

Christoph Waltz

as New Villains in Gravity Falls: Dipper and Mabel Return

Michelle Pfeiffer

as New Villains in Gravity Falls: Dipper and Mabel Return

Miranda Richardson

as New Villains in Gravity Falls: Dipper and Mabel Return

Imelda Staunton

as New Villains in Gravity Falls: Dipper and Mabel Return

Helena Bonham Carter

as New Villains in Gravity Falls: Dipper and Mabel Return

Jason Isaacs

as New Villains in Gravity Falls: Dipper and Mabel Return

Ralph Fiennes

as New Villains in Gravity Falls: Dipper and Mabel Return

Hugo Weaving

as New Villains in Gravity Falls: Dipper and Mabel Return

Mads Mikkelsen

as New Villains in Gravity Falls: Dipper and Mabel Return

Tom Hardy

as New Villains in Gravity Falls: Dipper and Mabel Return

Cillian Murphy

as New Villains in Gravity Falls: Dipper and Mabel Return

Til Schweiger

as New Villains in Gravity Falls: Dipper and Mabel Return

Stellan Skarsgård

as New Villains in Gravity Falls: Dipper and Mabel Return

Tim Roth

as New Villains in Gravity Falls: Dipper and Mabel Return

Nicole Kidman

as Priscilla Northwest in Gravity Falls (Live Action Film)

Manu Bennett

as New Villains in Gravity Falls: Dipper and Mabel Return

Sala Baker

as New Villains in Gravity Falls: Dipper and Mabel Return

Lana Parrilla

as New Villains in Gravity Falls: Dipper and Mabel Return