Calvin's allegedly imaginary friend, Hobbes). And Calvinball is a perfect reflection of Calvin’s worldview, as it melds pure imagination with utter chaos. Plus, the best part is that anyone can play Calvinball, as Calvin and Hobbes finally explains the rules (and they’re actually really simple).

Calvinball made its debut in the Calvin and Hobbes comic published on October 26, 1986. At the start of the comic, Calvin and Hobbes are right in the middle of an argument about the game before devolving into a full-on brawl. While readers don’t really get the chance to see Calvinball being played in its debut comic, the strip does tell fans everything they need to know about how the game is supposed to be played, and stands as the first time Calvinball ever appeared in Calvin and Hobbes.

Since then, Calvin and Hobbes have played Calvinball on numerous occasions, with Calvin even introducing the game to his babysitter, Rosalyn. However, even after seeing Calvinball played throughout the comic strips’ history, many fans are still left confused as to what the rules actually are - and that’s totally valid. Sometimes the two play with wickets and mallets, other times with volleyballs and balloons. So, what’s the deal with Calvinball? Well, the answer is actually deceptively simple: whatever the players can imagine.

Calvin and Hobbes’ Calvinball is a Masterclass in Imaginative Play

There are No Limits but the Player’s Own Imagination

To play Calvinball, all a player has to do is come up with rules meant to stump their opponent before their opponent does the same to them. Every made-up rule must be adhered to until the other player can come up with their own rule to counter it, and these rules have to apply to the objects used during any particular game.

Bill Watterson once said, “People have asked how to play Calvinball. It’s pretty simple: you make up the rules as you go.”

For instance, if Calvin and Hobbes are playing with flags and a soccer ball, Calvin can make up a rule that Hobbes has to take the flag to a nearby tree before Calvin can peg him with the ball, or else Hobbes’ penalty is to hop on one foot until he can come up with a rule to counter his penalty. And, if Hobbes is really good, the rule he comes up with to counter his penalty will result in a penalty for Calvin - and so on.

That’s just a hypothetical example based on what the Calvin and Hobbes comic strip has shown in the past, but there’s literally no limit to what the rules can be. That being said, there are a few permanent rules that must always be adhered to while playing Calvinball - two, to be exact.

There are Only 2 Rules That Must ALWAYS Be Followed While Playing Calvinball

Calvin and Hobbes Created These Rules at Different Points in the Comic’s History

While Calvinball requires no structure going into it, there are two rules that must be followed before players can begin:

• Players must always wear a mask.
• Calvinball cannot be played the same way twice.

The ‘mask’ rule was retroactively applied to practically every game of Calvinball ever played in the comic strip published on September 9, 1995, when Calvin is explaining to Rosalyn, “no one’s allowed to question the masks”, making it clear that wearing one is mandatory. The ‘can’t be played the same way twice’ rule is established in the Calvin and Hobbes strip published on May 27, 1990. However, that rule has always applied, as it’s virtually impossible to play a game the same way twice when the players are making up the rules as they go.

It might take a few tries to really get the hang of it, but once one does, Calvin and Hobbes’ deceptively simple Calvinball suddenly becomes a game that anyone can play - and it honestly sounds like a blast.