The marketing materials don't make it super clear but the "Merry & Myschivous Edition" includes a new expansion which should be included on-disc (not as a voucher).

-A@WZG

Has The Grinch grown to love Christmas, or should we be suspicious? Hmmm.

Snowboard, sleigh and even parachute through Who-ville, spreading Christmas cheer in The Grinch: Christmas Adventures – Merry & Mischievous Edition.

Collect presents and help The Grinch’s heart grow three sizes with awfully fun challenges alongside Max. Although it’s fun to be naughty, show the Whos you can be nice by preparing a festive feast.

Unlock Grinchy gadgets, solve puzzles, and earn rewards that will help you take on tin soldiers, gingerbread men, and dodge falling trees.

Will The Grinch save or steal Christmas? It’s up to you.

See the Ooutskirts of Who-Ville
Explore The Village, Town Hall, The Grinch Caves, Lakes and Sewers.

Stunt, Flip, or Glide
Showcase your skills using a jetpack, snowboard, sleigh and other customizable gadgets.

Missions With a View
Watch for collectables and enemies from the sky using Max’s Parachute.

New Challenges, More Rewards
Collect food and presents to earn jigsaws, art and accessories.

A Classic for Everyone
From visuals inspired by original books to easy controls for players.