Calvinball is a game invented by Calvin in which one makes the rules up as one goes along. Rules cannot be used twice. No Calvinball game is like another and involves wickets, mallets, volleyballs, and additional equipment as well as masks.
There is only one permanent rule in Calvinball: One can't play it in the same way twice. For example, in one game of Calvinball, the goal was to capture one's opponent's flag, whereas in a different game of Calvinball, the goal was to score points by hitting badmitton shuttlecocks against trees using a croquet mallet. An apparent rule in Calvinball is that one must wear a black mask and that one isn't allowed to question the mask. Another apparent rule is that any new rule made up by each player must be accepted.
Calvin created the game when he first became tired of organized sports. Although the first depicted game of Calvinball followed Calvin's failure to join the baseball team , the game appears in such a complete form there that it is likely Calvin and Hobbes had been playing the game for a long time beforehand.
The only hint at the true creation of the game comes from the last Calvinball strip, in which a game of football quickly changes into a game of Calvinball. Calvin remarks, "Sooner or later, all our games turn into Calvinball," suggesting a similar scenario that directly led to the creation of the sport.
Although all games of Calvinball are different, many of them seem to involve a ball (the Calvinball), masks, and pickets with numbers printed on them.
Key features of various games have included (in approximate order of appearance):
- Soccer balls
- Small signs with numbers
- The "Opposite Pole"
- The "Bonus Box"
- Croquet mallets
- Badminton shuttlecocks
- "Vortex spots"
- The "Boomerang Zone"
- A volleyball (the "Calvinball")
- Trees (as goalposts)
- The Calvinball theme song (see below)
- Water balloons
- Hobby horse
- The "Pernicious Poem Place"
- The Secret Base
Calvinball theme song
The Calvinball theme song made its only appearance in the penultimate Calvinball storyline. Calvin sings the lead while Hobbes sings backup with "Rumma-Tum-Tums."
- "Other kids' games are all such a bore!
- They've gotta have rules and they gotta keep score!
- Calvinball is better by far!
- It's never the same! It's always bizarre!
- You don't need a team or a referee!
- You know that it's great, 'cause it's named after me!"
After that, Calvin tells his babysitter to "feel free to harmonize with Hobbes on the Rumma-Tum-Tums".
The "Pernicious Poem"
The Poem that must be recited when one lands on the Pernicious Poem place is the fallowing:
"Here is a poem, now do as You're told! And here is a bucket of water, ice cold! Don't hesitate, and pour it on ME! Come on, do it A.S.A.P.!