The game begins with the laying down of the starting tile, which depicts the kinds of tapeworms stitched together. The first turn is either determined by who resembles a worm the most or at random. A player's turn includes the drawing and laying down of matching tiles, which continues until a matching head segment is laid down, thereby completing the tapeworm. Whichever player ends up with an empty hand wins the game.
There are special mechanics to propel a player forward, as well as cards intended to hinder the efforts of their opponents. These cards include: Cut, to sever a worm segment at play; Peek, to draw a card and replace it with another card from a hand; Hatch, to force an opponent to draw from the deck; Swap, to look at an opponent's hand and decide if cards should be traded; Dig, to draw a card from the deck and discard one from a hand. If a player creates a fully-connected ring of cards, it is identified as a Ringworm, resulting in the discarding of two cards from a hand.