Munchkin Hidden Treasures - Rules of Play says:

Munchkin Hidden Treasures consists of 78 individual cards for use in a variety of Munchkin games, with all of these cards previously being available solely in annual booster packs.

Sample cards include:

• Can of Worms from Munchkin
• Great Caesar's Ghost from Munchkin Bites
• Iron Chef R'Lyeh from Munchkin Cthulhu
• Mr. Spork from Star Munchkin

Munchkin Hidden Treasures Review:

Unfortunately we don't have a review of this item yet. Check back soon!