Twigs (voiced by David Tennant in series 1-2, and Mark Bonnar in series 3-5) is a silly and energetic Scottish acorn sprite who is Tom's sidekick and best friend, and frenemy of Chezz, who he usually encounters conflict. His catchphrases are "I am a Genius", "We're Doomed!" and "Wowzers!". He even turns into an acorn when he's hiding.